1A MEASUREMENT

10. Basic Units

1A10.10 standards of mass, etc Show models of the fundamental units of mass and length and a stop clock for time.
1A10.10 basic unit set Show a clock with a second sweep, meter and yard sticks, and kilogram and pound mass.
1A10.20 standards of mass Show students 1 lb, 1 kg, 1 slug masses.
1A10.20 standards of mass Show students 1 lb, 1 kg, 1 slug masses.
1A10.20 standards of mass Show sets of calibrated weights.
1A10.24 table of masses A table of masses covering the range from the universe to the electron.
1A10.28 conservation of mass Weigh a flask with Alka-Seltzer closed and open on a crude and accurate balance to aid in conservation of mass discussion.
1A10.29 TME and Glug The Technische Mass Einheit ("metric slug") = 10 Glugs.
1A10.30 standards of length
1A10.30 standards of length Put out standard yard and meter.
1A10.30 standards of length Standard meter and standard yard.
1A10.32 Airy points of a meter bar Support a rectangular bar at the specific points in order that the distance between engravings will not be altered by deflections due to the weight of the bar.
1A10.33 historical note Very interesting history of the development of the meter.
1A10.34 the new meter Wouldn't it be nice to start off six page article on the new meter with a concise definition of the new meter?
1A10.35 meter stick Set out a standard meter.
1A10.36 "1 nsec"
1A10.36 1 "nsec" Cut a length of meter stick to equal the distance light travels in one nsec.
1A10.38 body units
1A10.38 body units
1A10.40 clocks
1A10.40 clocks Set out a timer with a one second sweep, an hour glass, a metronome, etc.
1A10.45 WWV signal
1A10.45 WWV signal Listen to WWV and show the signal on an oscilloscope.
1A10.45 WWV signal Listen to WWV and display on an oscilloscope.
1A10.45 WWV Listen to WWV and show the signal on an oscilloscope.
1A10.46 WWV on your microcomputer Use WWV to set the clock on your microcomputer and determine how fast it runs.
1A10.48 Orrery Use an Orrery to show sidereal time.
1A10.49 Siderial time Two clocks on permanent display show Greenwich and Sidereal time.
1A10.50 one liter cube
1A10.50 one liter cube A one liter wood cube has cm square rules on each face and removable one cm sq and one cm x one dm blocks.
1A10.50 one liter cube Picture of a one liter cube.
1A10.55 mass, volume, and density
1A10.55 mass, volume, and density Compare wood and aluminum cubes, each with 10 cm sides, (equal volume). Compare a 10 cm aluminum cube with a 10 cm sq x 4 cm lead block (equal mass). Compare a is cm aluminum cube with a 10 cm sq x 4 cm aluminum block (equal density).
1A10.60 Avogadro's number box
1A10.60 Avogadro's number box A cube with sides of 28.2 cm has a volume of 22.4 l at STP.
1A10.60 Avogadro's number box
1A10.60 Avogadro's number box A 22.4 liter box to represent the volume of one mole at STP.
1A10.65 mole samples
1A10.65 mole samples Show mole samples of carbon, iron, copper, zinc, etc.
1A10.70 density samples
1A10.70 density samples One kg samples of lead, aluminum, water, wood each have 5 cm square bases. A one meter frame shows the size of approximately 1 kg of air.
1A10.71 Larry's density samples Add abstract in Handbook.FM

20. Error and Accuracy

1A20.10 Gaussian collision board
1A20.10 Gaussian curve marble board
1A20.10 Gaussian collision board Balls roll down a nail board into parallel chutes forming a probability curve similar to the distribution of molecular velocities.
1A20.10 Gaussian curve A commercial device for the overhead projector where ball bearings roll through an array of nails into parallel chutes.
1A20.20 coin flip
1A20.20 coin flips
1A20.25 dice
1A20.25 dice
1A20.31 contact time measurement Measure contact time of two hammers being struck together. A pulse generator is gated to a pulse counter while the hammers are in contact. Frequency of the pulse generator can be changed to vary accuracy.
1A20.41 vernier calipers Use commercial large scale verniers to show how they work. Also mentions large coordinate systems.
1A20.41 vernier calipers, etc Demonstration versions of the micrometer and vernier calipers.
1A20.42 vernier scale, slide rule for OH A slide rule and vernier scale made of clear plastic for use on the overhead projector.
1A20.50 weight judgment
1A20.50 wood and brass blocks A small heavy weight and a slightly lighter large wood block are passed around the class.
1A20.51 lead ping pong ball and foam chunk Students judge weight of a white lead filled ping pong ball and a chunk of black foam.
1A20.55 statistics on OH Transparent Lucite probability board for the OH projector. Construction details in the Appendix, p. 533.
1A20.60 reaction time
1A20.60 reaction time Cover 3/4 of a stop clock face. Push the stop button when the hand shows.
1A20.60 reaction time A large stop clock is covered by a disc with one quadrant cut out. Stop the clock as soon as you see the hand emerge.
1A20.60 reaction time Same as Mb-1a.

30. Coordinate Systems

1A30.10 XYZ Axes
1A30.10 XYZ Axes A stand holds large arrows. Also includes circular arrows that can be mounted on the vectors.
1A30.15 non-orthogonal frames A model for demonstrating the geometry of vectors in non-orthogonal frames.
1A30.21 Euler's angles A model that demonstrates the orientation of an arbitrarily oriented set of orthogonal axes with respect to another orthogonal set which is fixed.
1A30.22 Euler's angles - MITAC gyro model Use the MITAC gyro as a classroom model to illustrate Euler's angles.
1A30.30 polar coordinates
1A30.30 polar coordinates Need a demo to go with the xyz axes.
1A30.40 chalkboard globe
1A30.40 chalkboard globe Draw coordinates on a 20" plain globe.
1A30.41 blackboard hemisphere
1A30.41 blackboard hemisphere Half of a 20" dia. blackboard sphere.

40. Vectors

1A40.10 components of a vector Arrows define a three dimensional coordinate system. An arbitrary vector is viewed in the three planes.
1A40.10 components of a vector
1A40.10 components of a vector A three dimensional vector model on a large Lucite box. Diagrams.
1A40.10 3-D vector components Metal arrows define a three dimensional coordinate system. An arbitrary vector is viewed in the three planes.
1A40.13 components of a vector A Lucite frame for introducing vectors.
1A40.14 vector components animation
1A40.14 vector components Animation.
1A40.15 project components of a vector A horizontal arrow is shadow projected onto two screens at 90 deg. facing the class.
1A40.20 folding rule
1A40.20 folding rule A large version of the folding carpenter's rule of four 2' sections with painted arrows.
1A40.25 tinker toys
1A40.25 tinker toys Put out a box of tinker toys that includes arrow tips.
1A40.25 tinker toys A set of tinker toys is set out.
1A40.30 magnetic vector addition
1A40.30 magnetic vector addition
1A40.31 vector addition (parallelogram)
1A40.31 vector addition (parallelogram) Animation.
1A40.33 vector addition (head to tail)
1A40.33 vector addition (head to tail) Animation.
1A40.35 Vernier Vector Addition II
1A40.35 Vernier Vector Addition II Computer program.
1A40.40 resultant of vectors
1A40.40 resultant of vectors Show the variation in the magnitude of the resultant of two vectors with a change in the angle between them on the overhead projector. Construction details in Appendix, p. 537.
1A40.41 resultant of vectors Vector addition using elastic vectors on an open framework.
1A40.50 vector displacement An overhead projector device uses two compass needles to show that a vector remains invariant when displaced. Diagram.
1A40.70 vector dot products
1A40.70 vector dot products Animation.
1A40.75 vector cross products
1A40.75 vector cross product Animation shows vectors superimposed on a right hand.

50. Math Topics

1A50.10 radian disc A flexible strip of plastic equal to the radius is bent around the edge of a circle.
1A50.10 radian Show a flexible rod has a length equal to the radius of a large disc, then bend it around the circumference and mark off the radians.
1A50.10 radian A string is used to mark off radii on the circumference of a large disc.
1A50.10 radian disc A flexible strip of plastic equal to the radius is bent around the edge of a circle.
1A50.30 sine, cosine, and circle linkage Linkages connect a spot moving around a circle with spots moving orthogonally as the sine and cosine.
1A50.51 binary counter Working model of a binary counter with a scale of 32. Construction details in the Appendix, p. 533.
1A50.52 mechanical binary scaler A mechanical binary scaler with flipping wood blocks.
1A50.60 Dirac's strings models Some mechanisms to demonstrate Dirac's strings where turning through 360 degrees will not bring it back to the initial configuration.
1A50.60 discrete linear transformation Model of a discrete linear transformation where columns of water in a plexiglass cube are allowed to flow through a matrix plate into compartments models a discrete linear transformation.
1A50.65 sim. equations device A balancing meter stick as an analog device for solving linear simultaneous equations.
1A50.70 projection slide rule Make a projection slide rule with front and back scales mounted side by side.
1A50.80 integers as sum of reciprocals A general treatment of integer values of in the sum of reciprocals applicable to parallel resistors, series capacitors, spherical mirrors, thin lenses, etc.

60. Scalling

1A60.10 Powers of Ten "Powers of Ten" is a film covering scales from the universe to sub-atomic.
1A60.10 Powers of Ten "Powers of Ten" is a visual trip from covering scales from the universe to sub-atomic. It is available in film and videodisc versions.
1A60.20 scaling model for biological systems
1A60.20 two cows
1A60.20 scaling model for biological systems A wood "cow" with barely adequate legs stands and another scaled up by a factor of 5 collapses.
1A60.22 scaling - zoological domain The fundamentals of scaling in the zoological domain covering many animal characteristics.
1A60.30 2:1 scaling
1A60.30 2:1 scaling "Bridges" of the same geometry are scaled in every dimension by 2:1. Masses placed in the center of the bridges are also scaled 2:1.
1A60.40 scaling cube
1A60.40 scaling cube A large cube made up of 27 smaller ones is painted black on the outside. Knock the stack apart and show the increase in surface area by the preponderance of unpainted surfaces.
1A60.40 scaling cube Cut a cube painted black into 27 smaller cube. When dismantled, the unpainted surfaces show the increase in surface area.

1C MOTION IN ONE DIMENSION

10. Velocity

1C10.10 bulldozer on moving sheet/2D A bulldozer runs at constant speed on a moving paper to show how velocities add and subtract.
1C10.10 bulldozer on moving sheet The bulldozer on a moving sheet moves in the same or opposite direction as the moving sheet, not at a angle, to show addition and subtraction of velocities.
1C10.10 bulldozer on moving sheet Identical bulldozers run at constant speed, one on a moving paper, to show how velocities add and subtract.
1C10.20 PASCO dynamics cart
1C10.20 PASCO dynamics cart
1C10.21 measuring constant velocity Time a toy truck with a stop clock as it is pulled across the table at constant velocity in front of a meter stick.
1C10.22 photographing uniform motion Take an open shutter photo of a toy tractor moving a blinky.
1C10.25 air track and glider
1C10.25 air track and glider
1C10.25 constant velocity (airtrack) Dots are superimposed on the screen every half second to mark the position of the air glider.
1C10.26 velocity -air track and glider Measuring air track cart velocity: stopwatch and meter stick, spark recorder, photo interrupt.
1C10.27 velocity -air track and glider
1C10.27 velocity -air track and glider Level air track with the Pasco photogate timer system. Use one or two timers.
1C10.30 approaching instantaneous velocity
1C10.30 approaching instantaneous velocity An air cart is given a reproducible velocity by a solenoid kicker. Flags of decreasing length interrupt a photo timer.
1C10.30 approaching instantaneous velocity A ball breaks two foils to start and stop a timer. Change spacing of gates to approach instantaneous velocity.
1C10.32 strobed disc Look at a fluorescent spot on a 1725 RPM disc with a stroboscope at multiples of the frequency to demonstrate the limiting process.
1C10.33 speed at a point Take a picture of a light bulb pendulum with a strobed camera.
1C10.51 terminal velocity A mechanical device rolls down an incline with a terminal velocity.
1C10.55 terminal velocity tube A marble rolling down a tube of water at a slight incline reaches terminal velocity allowing slow constant velocity to be measured.
1C10.60 muzzle velocity
1C10.60 muzzle velocity - foil Graphite rods are broken to switch an oscillator in and out of a counter circuit.
1C10.60 muzzle velocity - foil Use the circuit in AJP 44(9),85 with the breaking foil method of measuring muzzle velocity.
1C10.60 muzzle velocity - foil Using the apparatus by Blackburn and Koenig, AJP 44,855(1976), to measure the muzzle velocity of a rifle.
1C10.60 muzzle velocity - foil The bullet passes through two aluminum foil strips. The signal is shown on an oscilloscope.
1C10.60 muzzle velocity - foil Bullet breaks two metal foils triggering a timer.
1C10.60 muzzle velocity - foil Aluminum foil triggers 1 m apart start and stop an electronic timer. Construction details.
1C10.61 muzzle velocity - photogate timer Measure the speed of a bullet with eight crisscrossing LED beams with the detectors connected to an eight input OR gate.
1C10.61 muzzle velocity - photogate Details of a photoelectric triggering circuit good to a few microseconds.
1C10.62 time of flight An inexpensive circuit useful in time-of-flight velocity measurements for bullet velocity with the ballistic pendulum demonstration of momentum conservation. Mechanical construction considerations are outlined.
1C10.62 time of flight An apparatus measures the time of flight of the projectile fired from the Blackwood pendulum apparatus by timing signals from two microphones. Circuits are included.
1C10.63 RC bullet timer A capacitor is discharged to a ballistic galvanometer during the time the bullet passes between two gates. Diagrams and theory.
1C10.65 muzzle velocity - disc
1C10.65 muzzle velocity - disk An air gun is fired through two rotating cardboard discs separated by some distance.
1C10.65 muzzle velocity - disk Shooting a bullet through two rotation discs.
1C10.65 muzzle velocity - disk Fire a bullet through two discs rotating on the same shaft.
1C10.66 muzzle velocity - strobe photo Sets of contacts two meters apart trigger a strobe which illuminates a spinning wheel marked with a radial line. Measure the angle on the photograph.
1C10.71 low velocity Project the minute hand of a clock.
1C10.72 velocity table A table of velocities ranging from continental drift to the speed of light.

20. Uniform Acceleration

1C20.10 penny and feather Drop a penny and feather in a glass tube, first full of air and then evacuated.
1C20.10 penny and feather Drop a penny and feather in a glass tube, first full of air and then evacuated.
1C20.10 penny and feather Invert a large glass tube containing a feather and bit of lead.
1C20.10 penny and feather Dropping the feather and coin in a vacuum.
1C20.10 guinea and feather Metal and paper discs are placed in identical tubes.
1C20.11 drop feather on book
1C20.12 hammer and feather on Moom
1C20.15 drop lead and cork balls
1C20.15 cork and lead ball drop
1C20.15 drop cork & lead balls Hint on how to drop a heavy and light object simultaneously with one hand.
1C20.15 drop iron and wood balls Iron and wood balls are dropped simultaneously.
1C20.16 drop ball and paper
1C20.16 drop ball and paper Drop a ball and sheet of paper, then drop a ball and a wadded sheet of paper.
1C20.17 heavy and light balls pedagogy Try asking what height the light ball must be dropped from so it hits the floor at the same time as the light.
1C20.20 equal time equal distance drop
1C20.20 equal time equal distance drop Climb a ladder and drop two long strings with balls - one with equal distance intervals and the other with equal time intervals.
1C20.20 equal time equal distance drop String and Sticky Tape Series: directions for simple apparatus.
1C20.20 equal time equal distance drop Drop a long string of balls with spacing of 1,4,9,16.
1C20.20 equal time equal distance drop Drop a string with wood blocks tied at 1,4,9,16 unit intervals.
1C20.20 equal time equal distance drop Drop a string with a series of lead balls attached.
1C20.20 string and weights drop Drop strings with weights.
1C20.30 inclined air track
1C20.30 inclined air track Place risers under one end of an air track. Use photogate timers to measure the velocity at two points.
1C20.30 inclined air track Timing on an inclined air track: spark recording, photoelectric, periodic impact.
1C20.30 inclined air track Interrupted photocell times a cart at the top and bottom of an incline.
1C20.30 constant acceleration Dots marking the position of the glider are superimposed on the screen as the glider accelerates down an inclined air track
1C20.31 inclined air track Use a stop clock and meter stick with the inclined air track.
1C20.35 inclined air track Data for graphs of acceleration, velocity, or displacement as a function of time is obtained from a cart on an inclined air track as it accelerates down and rebounds. Details for a timing device using two spring contacts.
1C20.36 inclined air track Record a cart on an inclined air track with strobe photography.
1C20.40 blinky track
1C20.40 blinky track Lights that flash every second are placed along an inclined and horizontal track such that they flash at the moment the ball passes.
1C20.40 acceleration "v" track Use a 1" x 1" extruded aluminum angle for an acceleration track raceway.
1C20.40 blinky track A ball rolls down a sloped track onto a flat track. A series of lights blinking every second is mounted on the track at intervals such that the ball passes as the light blinks.
1C20.40 blinky track Lights that flash every second are spaced along an incline and horizontal track such that they are flashing at the moment the ball passes.
1C20.40 blinky track The original blinky track.
1C20.41 blinky track with graphs
1C20.41 blinky track with graphs Two sets of magnetic arrows are transferred from the blinky track to a magnetic blackboard. The arrows graphs show the position at blinks and the change in position at blinks.
1C20.41 rolling ball on incline Additions to the blinky track: magnetic strips can be removed from the track showing all d's, delta d's, and delta v's. Place these strips vertically to show position, velocity, and acceleration vs time. Graphs are simulations on disc but real at U of Wash.
1C20.42 blinky track - strobe photo Use a strobe and camera to record a ball rolling down an incline and across a flat.
1C20.43 ball on an incline A ball is accelerated down an incline onto a horizontal track where the velocity is measured.
1C20.43 ball on an incline with seconds pend A seconds pendulum is released when the ball enters the horizontal track (M-82) and is placed so it knocks the ball off the track.
1C20.44 inclined wire A taut inclined wire forms the incline.
1C20.44 car on an inclined wire A long wire is stretched diagonally across the chalkboard with chalk marks at every meter. A student times a low friction car as it accelerates to various marks.
1C20.45 ball on an incline A simple demonstration using a ball bearing rolling down the grove of a plastic meter stick. Analysis included.
1C20.45 slow roller on incline A solid wheel turning on a small axis rolls down an incline. The translational velocity is slow enough to make easy accurate measurements.
1C20.45 ball on an incline Rolling a ball down an incline starting at 1/4 the way up and all the way up.
1C20.46 car on an incline A car on an incline is timed from release until the end of a measured distance.
1C20.50 Duff's plane A chalk ball oscillates as it rolls down a trough in a 2x6.
1C20.50 Duff's plane A ball leaves a trail as it oscillates back and forth while rolling down a chalk covered trough.
1C20.61 dynamometer A simple dynamometer rides a cart on a track.
1C20.71 photographing acceleration Take an open shutter strobe wheel photo of a small fan cart.

30. Measuring g

1C30.10 free fall timer A ball is timed as it drops .5m, 1m, 1.5m, or 2m.
1C30.10 free fall timer A ball is timed as it drops .5m, 1m, 1.5m, or 2m.
1C30.11 dropping balls A latching relay system for turning a standard timer on and off for the dropping ball experiment. Use two independent measurements to eliminate the delay factor.
1C30.12 dropping balls Use a photo interrupt system to time a falling ball. Details in appendix to demo 10-2.18.
1C30.13 dropping balls - release A clever device to replace the standard electromagnet release for timing a dropping ball.
1C30.13 dropping balls By replacing optical position sensors with electrical contact switches and by using an integrated-circuit timer with digital readout, the time required for a ball bearing to fall may be measured consistently to about 0.1 msec. The acceleration of gravity may then be determined to better than one part per thousand.
1C30.13 accurate release mechanism A new release mechanism with 10 ms accuracy.
1C30.14 free fall timer - stopwatch mod. Modify a commercial lap timer/stopwatch. Interface circuit and construction details.
1C30.15 little big ball dropper
1C30.15 big ball dropper
1C30.16 dropping balls A ball is released by an electromagnet and a clock started. The catcher stops the clock and can be set at different heights.
1C30.17 Welch free fall apparatus Describes an old Welch free fall apparatus.
1C30.18 big ball dropper
1C30.20 big big ball dropper
1C30.20 tall big ball dropper
1C30.21 dropping balls Dropping a ball through a system of mirrors interrupts a light beam several times. Photocell output is displayed on a scope.
1C30.22 induction method Drop a magnet through several equally spaced coils of wire. Examine the induced voltage on an oscilloscope. Circuit included.
1C30.25 dropping balls in air Light and heavy balls are dropped through a multiple pass light beam and the output is shown on an oscilloscope.
1C30.30 falling slab A slab of wood is dropped by a ink squirter which leaves lines at equal time intervals.
1C30.31 ink jet marker A rotating ink jet sprays a paper sleeve on a falling meter stick.
1C30.33 dropping balls - photo Take a picture of a dropping ball illuminated by a strobe.
1C30.33 dropping balls - photo Photograph a dropping light bulb with a strobed disc.
1C30.40 falling drops
1C30.40 mercury drops A falling mercury drop generator and an electronic timing circuit conveniently and automatically generates a large number of data in a short period of time, yielding results with a high degree of precision.
1C30.41 falling drops A strobe illuminates water dripping from a faucet at an uniform rate.
1C30.42 falling drops A machine to make a stream of falling bubbles which are illuminated by a strobe light.
1C30.43 falling drops Steel balls are dropped at regular intervals and illuminated with a strobe. Diagrams and pictures.
1C30.44 synchrodropper Design for a 60 Hz stable synchrodropper.
1C30.46 "videostrobe" with falling drops Use the 60 Hz refresh rate of a video monitor to strobe falling drops by adjusting the rate to 60 Hz and having the stream fall past the screen.
1C30.55 catch a meter stick
1C30.55 catch a meter sitck Have one student drop a meter stick and use the distance it drops before another students catches it to determine the reaction time.
1C30.55 catch a dollar Have a student try to catch a dollar starting with the fingers at the midpoint.
1C30.55 catch a meter stick Drop a meter stick and have a student catch it. Distance can be converted to reaction time.
1C30.55 catch a meter stick Drop a meter stick and have a student catch it.
1C30.55 reaction time falling meter stick Have a student catch a falling meter stick and relate the distance dropped to the reaction time.
1C30.61 rotating turntable Drop a ball on a phonograph turntable. Get time from the range.
1C30.61 rotating turntable Microswitch triggers dropping ball onto rotating turntable.
1C30.63 pendulum timed free fall A pendulum released from the side hits a ball dropped from the height that gives a fall time equal to a quarter period of the pendulum.
1C30.66 many bounce method Time a bouncing ball for many bounces and determine g using the coefficient of restitution.

1D MOTION IN TWO DIMENSIONS

10. Displacement in Two Dimensions


1D10.10 ball in a tube Start with a ball on a string at the bottom of a vertical tube. Hold the string while moving the tube horizontally.
1D10.10 ball in a tube A ball on a string is placed in a tube and the tube displaced. The resultant is quite apparent.
1D10.10 ball in a tube Ball on a string in a hydrometer jar.
1D10.10 ball in a tube A ball on a string is placed in a clear tube and the string is displaced.
1D10.10 ball in a tube A bead is pulled vertically along a rod in a frame that is pulled horizontally.
1D10.10 ball in a tube A ball on a string is placed in a horizontal tube which is raised while holding the free end of the string on the table.
1D10.10 velocity vector addition The ball in a tube done horizontally on the table viewed from above with the camera.
1D10.20 cycloid generator
1D10.20 cycloid generator A disc with a piece of chalk at the edge is rolled along the chalk tray.
1D10.20 cycloid generator A hoop with a piece of chalk fastened to the circumference is rolled along the chalk tray.
1D10.20 cycloid generator Large and small cylinders are joined coaxially. A spot on the larger cylinder moves in a cycloid when the smaller cylinder is rolled on its circumference.
1D10.30 inversor A mechanical device that transforms rotational motion into rectilinear motion.
1D10.31 rotation and relative translation A three pronged spider in a six slotted wheel.
1D10.32 rotation and translation Two blocks - one with slots and the other with pins.
1D10.40 mounted wheel
1D10.40 mounted wheel A large disc marked with a radial line turns about its axis.
1D10.50 ball on the edge of a disc
1D10.50 ball on the edge of a disc A ping pong ball is stuck on the edge of a vertical rotating disc.
1D10.55 circular motion on the OH A device to turn a clear plastic disc at variable speed on the overhead projector.
1D10.55 balls on a disc on the OH proj A motorized acrylic disc with three holes for steel balls rotates on an overhead projector.
1D10.60 measuring angular velocity Use an electronic strobe to measure the angular velocity of a fan blade or other rotating objects.
1D10.70 disc on cart A spinning disc mounted on a cart has a rectilinear pattern of dots. The center dot is stationary while the cart is stationary, a different dot appears stationary while moving the cart in a large circle, or while translating the cart along a track.
1D10.71 spots on a globe An inclined globe with spots is spun, rotated in an orbit while not spinning, and both rotated and spun. The spots form parallel lines perpendicular to the various angular velocity vectors.
1D10.72 spots on a globe A globe with random spots rests on rollers driven independently at variable speeds to show instantaneous center of rotation.

15. Velocity, Position, and Acceler

1D15.01 showing acceleration see 1G20.75
1D15.10 ultrasonic detector and students Have a student walk to and from a sonic ranger while observing plots of position, velocity, and acc.
1D15.10 sonic ranger and students Have a student walk toward and away from a sonic ranger while observing plots of position, velocity, and acceleration on a projection of the Mac.
1D15.12 Hobbie film loop - AAPT
1D15.12 Hobbie films - AAPT
1D15.15 kick a moving ball
1D15.15 kick a moving ball Kick a moving soccer ball on the floor or hit a moving croquet ball on the lecture bench with a mallet.
1D15.20 high road low road
1D15.20 high road low road Two balls race - one down a slight incline and the other down the same incline but including a valley.
1D15.20 high road low road Two objects start at the same velocity, one moves straight to the finish, the other traverses a valley. The problem: which wins?
1D15.30 catching the train
1D15.30 catching the train A ball accelerating down an incline catches and passes a ball moving at constant velocity on a horizontal track.
1D15.35 passing the train
1D15.35 passing the train A ball accelerates down an incline with a stripped rope moving at constant velocity in the background. The moment the ball has the same velocity as the rope is strikingly obvious. Repeat with the rope at a different constant velocity.
1D15.36 several ball and incline demos This McDermott article contains several ball on incline races to help distinguish the concepts of position, velocity, acceleration.
1D15.40 Galileo's circle
1D15.40 Galileo's circle Several rods are mounted as cords of a large circle with one end of each rod top center. Beads released simultaneously at the top all reach the ends the rods at the same time.
1D15.40 Galileo's circle Small balls roll down guides that form chords of a large inclined circle. A single click marks simultaneous arrival.
1D15.40 Galileo's circle Beads are released simultaneously to slide along cords of a large circle.
1D15.41 sliding weights on triangle
1D15.41 sliding weights on triangle Lengths and angles of a wire frame triangle are chosen so that beads sliding down the wires traverse each side in the same time.
1D15.45 brachistochrone track Three tracks - straight line, parabola, and cycloid are mounted together. Triggers at each end control a timer. Details.
1D15.50 brachistochrone
1D15.50 brachistochrone Each end of a track forms a brachistochrone. Balls released at any height on the brachistochrones reach the middle at the same time.
1D15.50 brachistochrone Two balls released on opposite sides of a cycloid always meet in the middle regardless of handicap. The ball on the cycloid always beats the ball on the incline.
1D15.51 brachistochrone is a tautochrone History of the brachistochrone as a tautochrone.
1D15.52 brachistochrone On constructing a large brachistochrone.
1D15.53 cycloidal slide track Use the brachistochrone and tautochrone properties of a cycloid to make an actual slide track in amusement parks.
1D15.54 brachistochrone Solution to the brachistochrone problem.
1D15.55 triple track
1D15.55 tripple track Balls roll down an incline, brachistochrone, and parabola. The ball on the brachistochrone wins.

40. Motion of the Center of Mass

1D40.10 throw objects A light disc contains a heavy slug that can be shifted from the center to side. Mark the center of mass.
1D40.10 throw objects Mount battery powered lights on styrofoam shapes and throw them in the air.
1D40.10 throw objects A light wooden disc contains a heavy slug that can be shifted from the center to the side.
1D40.10 throw objects Throw a slab of styrofoam with lights placed at the center of gravity and away from the center of gravity.
1D40.11 throw objects A disc with a internal sliding weight has spots painted on opposite sides marking the center of mass in the two cases.
1D40.11 throw objects Discs with movable and stationary center of mass and a "bulls eye" painted on each side, one off center.
1D40.11 center of mass disc Throw a disc with uniform distribution and then offset the center of mass.
1D40.12 throw hammer Mark the center of gravity of a hammer with a white spot. Throw it in the air and attach it to a hand drill to show it rotating smoothly.
1D40.13 throw objects A bunch of junk is tied together with strings and thrown across the room.
1D40.15 loaded bolas
1D40.15 loaded bolas This was in the Physics Teacher but I haven't got to it and I've never done it so I can't describe it well at this time.
1D40.20 spinning block
1D40.20 spinning block A large block of wood with magic markers located at and away from the center of mass. Place the block on a large sheet of paper and hit off center with a hammer.
1D40.20 spinning block A large wood block has two holes for felt tipped pens, one on the center of mass. Put the block on paper and hit it down the paper.
1D40.21 air supported dumbell Two dry ice pucks on the ends of a bar form a dumbbell that rides on a sheet of plate glass. Use a cue stick to hit it on and off the center of mass.
1D40.21 spinning block Use a pool cue to hit a dumbbell double dry ice puck on or off the center of mass. Also shoot a 22 into a gas supported block on or off the center of mass.
1D40.22 air table center of mass
1D40.22 air table center of mass A weighted block glides across an air table.
1D40.25 photographing the center of mass Make an open lens photo of a system of to masses connected by a rod and the center of mass will be apparent.
1D40.25 photographing center of motion Photographing the center of velocity of a variety of rigid bodies.
1D40.25 spinning block Strobed photo is taken of a irregular object translating and rotating on a air table.
1D40.30 throw the dumbell A dumbbell with unequal masses is thrown without rotation when the force is applied at the center of mass.
1D40.31 throw the dumbell Stick unequal size corks in knitting needle, place a cord under at the center of mass, and jerk it into the air.
1D40.35 earth moon system
1D40.35 Earth-Moon system An earth-moon system hanging from a string is used to demonstrate the earth's wobble.
1D40.35 Earth-Moon system Two unequal masses are fastened to the ends of a rigid bar. Spin the system about holes drilled in the bar at and off the center of mass.
1D40.35 Earth-Moon system Pucks of different mass are held together by a string while spinning on the air table.
1D40.35 Earth-Moon system An Earth-Moon system is rotated from a hand drill on and off the center of gravity.
1D40.50 air track pendulum glider
1D40.50 air track pendulum glider A double pendulum hangs from an air track cart with a mounted spot marking the center of mass. Set the system in oscillation and the spot will remain still or translate smoothly.
1D40.50 air track pendulum glider A pendulum with a massive bob is attached to an air cart.
1D40.50 air track pendulum glider A heavy pendulum on a light cart.
1D40.50 air track pendulum glider A double pendulum on an air cart has total mass equal to the cart. A marker placed on the pendulum at the center of mass is stationary as the system oscillates.
1D40.51 momentum pendulum A pendulum support is free to move on rollers as the pendulum swings back and forth.
1D40.52 momentum pendulum car Mount a heavy pendulum on a PSSC car and then have the students imagine the pendulum scaled up to be the earth.
1D40.55 air track inchworm
1D40.55 air track inchworm A leaf spring couples two air track gliders.
1D40.55 air track inchworm The center of mass of two carts coupled with leaf springs is marked with a light or flag. Show oscillation about the center of mass or constant velocity of c of m.
1D40.55 air track inchworm Two carts on a track are coupled with a leaf spring and elastic. A light is mounted on the elastic at the center of mass.
1D40.56 momentum cars Two cars are attached together by a elastic band fastened to a motorized eccentric on one car. The point of no motion can be indicated by a pointer and changed by weighting one car.
1D40.58 rotor on a cart Balls of equal or unequal mass can be screwed on the ends of a rod rotating horizontally about its center. The assembly is mounted on a cart on a track. The cart oscillates if the balls are of unequal mass.
1D40.60 satellite oscillation Discussion of the LDEF satellite (30'x14'dia.) as an example where the distinction between the center of mass and center of gravity is important.
1D40.70 two circle roller Two disks, partially interlocking at right angles, roll with a wobble but with a constant height center of mass.
1D40.71 non-round rollers Two types of weird rollers: one in which the center of mass remains at a uniform distance from the surface as it wobbles down an incline, and two which although non round have a constant diameter.

50. Central Forces

1D50.10 ball on a string Tie a lightweight ball to a sting and twirl around in a vertical circle.
1D50.10 ball on a string Tie a whiffle ball to a sting and twirl around in a vertical circle.
1D50.15 arrow on a disc
1D50.15 arrow on a disk Mount an arrow tangentially on the edge of a rotating disk.
1D50.20 whirligig
1D50.20 whirligig A large ball and a small ball fastened to opposite ends of a string which is threaded through a handle.
1D50.20 centripetal force apparatus Use a glass tube for the holder and rubber stoppers for the masses.
1D50.20 whirligig A large and small ball are on opposite sides of a string threaded through a handle.
1D50.20 whirligig Two balls - 1 kg, 100 g - are attached to the ends of a 1 m string passing through a small hollow tube. Twirl a ball around your head.
1D50.20 ball on cord A string with a rubber ball on one end passes through a plastic sleeve and weights are attached to a loop at the other end.
1D50.23 whirlygig Apparatus Drawings Project No. 25: Construction of a low friction conical pendulum.
1D50.23 whirligig The front axle of a bike is used for a whirligig support.
1D50.25 conical pendulum
1D50.25 conical pendulum A ceiling mounted bowling ball pendulum is used as a conical pendulum.
1D50.25 conical pendulum A ball on a cord is rotated mechanically at a steady slow speed.
1D50.26 plane on a string
1D50.26 plane on string A model plane flies around on a string defining a conical pendulum.
1D50.27 conical pendulum Motorized triple bifilar coaxial conical pendula are used to demonstrate critical period.
1D50.28 conical pendulum The main bearing of a conical pendulum is from a bicycle wheel axle. See also under whrilygig (AJP 30,221)
1D50.28 conical pendulum The front wheel axle of a bike is used as a good bearing for a conical pendulum where the string tension is set by a counterweight. See AJP 31(1),58.
1D50.29 conical pendulum game Swing a conical pendulum so it will strike a peg directly under the support on some swing other than the first.
1D50.30 carnival ride model
1D50.30 canival ride model A toy person is held on a vertical card at the edge of a turntable when the turntable is spun fast enough.
1D50.30 roundup A toy person stands on the inside wall of a rotating cylinder.
1D50.37 swinging up a weight An arrangement whereby a swinging 500 g weight picks up a 1000 g weight.
1D50.40 pail of water Swing a bucket of water in a verticle circle over your head.
1D50.40 pail of water, pail of nails Swing a bucket of water in a vertical circle over your head. If nails are used, they can be heard dropping away from the bottom of the can.
1D50.40 pail of water A pail of water is whirled around in a vertical circle.
1D50.40 pail of water Swing a bucket of water over your head.
1D50.40 whirling bucket of water Rotate a bucket of water in a vertical circle.
1D50.45 penny on a coat hanger
1D50.45 penny on a coathanger
1D50.45 penny on the coathanger Place a penny on an elongated coat hanger and rotate around your finger.
1D50.45 penny on the coathanger A penny is balanced on the hook of a coat hanger. The coat hanger is twirled around your finger and the penny doesn't fly off.
1D50.45 penny on the coathanger The wire coat hanger is whirled about the vertical plane by the hook without dislodging the dime on the middle of the lower bar.
1D50.45 penny on the coathanger Place a coin on the coat hanger and rotate it about the finger.
1D50.45 coin on coat hanger A coin is placed on the flat of the hook of an elongated coat hanger and twirled around.
1D50.48 balls on a propeller
1D50.48 balls on a propeller Balls sit in cups mounted on a swinging arm at .5 and 1.0 m. Calculate the period necessary to keep the ball in the outer cup and swing it around in time to a metronome.
1D50.50 Welch centripetal force
1D50.50 Welch centripetal force The angular velocity and mass needed to stretch a spring a certain distance are compared.
1D50.50 Welch centripetal force review Uses no motor, self contained static force measurement.
1D50.50 Welch centripetal force The angular velocity and mass needed to stretch a spring a certain distance are compared.
1D50.51 Welch centripetal force modification Two modifications to the apparatus.
1D50.51 Welch centripetal force A modification to improve the Sargent-Welch 9030 centripetal force apparatus.
1D50.51 Welch centripetal force modification Improvements to the Welch centripetal force apparatus.
1D50.53 variable centripetal force A new design for the apparatus that allows any two of the three variables of mass, angular velocity, and distance to be kept constant.
1D50.53 Cenco centripetal force A relay starts the counter and clock so three hands are not needed when using the Cenco 74470 apparatus.
1D50.53 Cenco centripetal force Lab apparatus used as a demonstration.
1D50.54 Cenco centripetal force modification Replace the screw adjustment for the fixed end of the spring with a movable plate.
1D50.55 hand rotator Two 2000 g spring balances are mounted on a rotator. Equal masses are attached to each and readings are taken at some rotational velocity.
1D50.60 banked track
1D50.60 banked track Need Demo.
1D50.60 banked track A steel ball rolled down an incline into a funnel reaches an equilibrium level where it revolves in a horizontal plane.
1D50.62 ball in a megaphone Throw a ball into a megaphone and it turns around and comes out the wide end.
1D50.65 banked track A turntable can be rotated at various angular frequencies. Objects can be placed at different radii. A small platform can be attached which will swing out to the correct slope for any angular velocity. A device for measuring force is also shown.
1D50.69 puzzle Two balls in a box must be caught in end pockets simultaneously.
1D50.70 rolling chain
1D50.70 rolling chain A loop of chain is spun up on a disc and released to roll down the lecture bench as a rigid hoop.
1D50.70 rolling chain A flexible chain is spun on a motorized pulley. When it is released, it maintains rigidity as it rolls down the lecture bench.
1D50.70 rolling chain A loop of chain is brought up to speed on a motorized disc and when released rolls down the lecture bench over obstacles.
1D50.70 rolling chain A loop of chain spun on a wheel and forced off remains rigid for some time.
1D50.70 spinning chain Spin a flexible chain rapidly enough that it acts as a solid object.

52. Deformation by Central Forces

1D52.10 flattening earth
1D52.10 flattening earth A hand crank spins a globe made of flexible brass hoops.
1D52.10 flattening Earth Flexible hoops flatten when spun on a hand crank rotator.
1D52.10 centrifuge hoops A flexible hoop becomes oblate as it is rotated.
1D52.11 flattening Earth Spin deformable balls. A clay/glycerin ball will burst, a sponge rubber ball will deform greatly.
1D52.17 empty jug by swirling A jug will empty faster when swirled.
1D52.20 water parabola
1D52.20 water parabola
1D52.20 water parabola A rectangular plexiglass box partially filled with colored water is rotated. The parabolic shape is clearly seen.
1D52.20 water parabola A flat sided tank half full of water is rotated on a platform.
1D52.20 water parabola A small self strobed rotating plexiglass container is used to project the water parabola.
1D52.20 water parabola A glass cylinder half filled with colored water is spun on a rotating table.
1D52.20 parabolid of revolution A cylindrical container with some water is rotated at a constant speed.
1D52.21 rotating water troughs
1D52.21 rotation water troughs Two water containers are mounted on a rotating table. A rectangular container mounted radially shows half a parabola, and another formed in an arc of constant radius stays level.
1D52.23 rotating manometer Tubing constructed in an "E" shape on its back is partly filled with water and rotated.
1D52.24 rotating manometer A U shaped manometer is mounted with one of its arms coincident with the axis of a rotating table.
1D52.26 project mercury parabola Spin a dish of mercury and image a light bulb on the ceiling.
1D52.30 balls in water centrifuge
1D52.30 balls in water sentrifuge Cork and steel balls are spun in a curved tube filled with water.
1D52.30 balls in water centrifuge Wood balls in two curved tubes, air and water filled, are rotated.
1D52.30 balls in water centrifuge Spin a bent glass tube filled with water that contains two wood or steel balls.
1D52.30 balls in water centrifuge Spin a bent glass tube filled with water containing cork and aluminum balls.
1D52.30 balls in water centrifuge A glass bowl containing water, a steel ball, a cork ball is spun.
1D52.30 corks in water centrifuge Spin a semicircular tube filled with water containing two corks.
1D52.31 inertial pressure gradient A bubble in a tube goes to the center when whirled in a horizontal circle.
1D52.31 centrifuge A long thin tube containing a wood plug is rotated horizontal while either filled with water or empty.
1D52.31 balls in water centrifuge A long thin tube containing a brass ball, ping pong ball, and water is rotated.
1D52.33 cork and ball rotating in water One cork is tied to the bottom, one ball is tied to the top of two cylinders full of water at the ends of a rotating bar.
1D52.33 rotating corks in water Corks tied to the bottom of two jars full of water are first translated on a cart and then put on a pivot and rotated about the center.
1D52.34 car picture A picture taken from inside a car of a candle, CO2 balloon, H2 balloon as the car is driven in uniform circular motion.
1D52.35 water and mercury centrifuge
1D52.35 mercury/water centrifuge A globe with water and mercury on a hand crank rotator.
1D52.35 mercury/water centrifuge A spherical glass bowl is spun and mercury forms a equatorial band with water above and below.
1D52.35 water and mercury centrifuge Water and mercury spin in a glass sphere.
1D52.36 centrifuge Diagram for building a projection cell centrifuge.
1D52.37 centrifuge A hand cranked test tube centrifuge.
1D52.38 the full skirt Spin a doll with a full skirt or kilt. Cheap thrills.
1D52.40 rotating candle
1D52.40 rotating candle A candle is placed on a turntable and covered with a large plexiglass hemisphere.
1D52.40 rotating candle Make the rotating candle out of meter sticks and candles.
1D52.40 central pressure gradients A candle rotates in a chimney on a turntable.
1D52.40 rotating candle A lighted candle in a chimney goes around on a dry ice puck string attached by a string to a pivot.
1D52.40 rotating candle A lighted candle in a chimney lamp on a rotating table will point to the center.
1D52.40 rotating candle Lighted candles in chimneys are rotated about the center of mass.
1D52.45 geotropsim Grow corn or wheat on a rotating turntable two weeks before class.
1D52.50 paper saw
1D52.50 paper saw A 6" paper disc placed on a dremmel tool cuts another sheet of paper.
1D52.50 paper saw Typewriter paper will cut through other paper, Bristol board will cut through wood when spun at high speeds.
1D52.60 rubber wheel A sponge rubber wheel with one spoke cut is rotated at high speed and viewed under stroboscopic light.
1D52.61 rotating rubber wheel
1D52.61 rotating rubber wheel A rubber wheel stretches to a larger radius when spun.
1D52.70 wobbling Christmas tree toy A Lagrangian-effective potential solution explaining the behavior of this toy.
1D52.90 centripetal-centrifugal discussion A final (?) note on the topic from the editor.

55. Centrifugal Escape

1D55.10 broken ring
1D55.10 broken ring A ball is rolled around the inside of a large open metal hoop. Students predict where the ball will go when it reaches the opening.
1D55.10 circle with gap Roll a ball around a circular hoop with a gap.
1D55.11 the big omega
1D55.11 the big omega A large wood circle with a gap is used with a bocce ball.
1D55.15 release ball on a string
1D55.15 cut the string Cut the string while swinging a ball overhead.
1D55.16 slingshot A David and Goliath type slingshot.
1D55.20 grinding wheel
1D55.20 grinding wheel Watch the path of sparks flying off a grinding wheel.
1D55.20 grinding wheel Show the sparks coming off a grinding wheel.
1D55.20 grinding wheel Sparks fly off a grinding wheel.
1D55.23 spinning disc with water
1D55.23 spinning disc with water Red drops fly off a spinning disc leaving traces tangent to the disc.
1D55.30 falling off the merry-go-round
1D55.30 falling off the merry-go-round Large turntable with different surfaces.
1D55.30 falling off the merry-go-round A turntable is rotated until objects slide or tip over.
1D55.30 rotating disc with erasers Place erasers on a disc at various radii and rotate until they fly off.
1D55.31 falling off the merry-go-round Line up quarters radially on a rotating platform and spin at varying rates.
1D55.33 train wrecks Pictures of train wrecks at curves and some calculations.
1D55.50 air pump Three mutually perpendicular discs are rotated about the intersection of two and air is drawn in the poles and expelled at the equator.

60. Projectile Motion

1D60.05 ball to throw
1D60.05 ball to throw Provide a large nerf ball, tennis ball, soft ball, or whatever ball is requested.
1D60.10 howitzer and tunnel A ball fired vertically from cart moving horizontally falls back into the muzzle.
1D60.10 howitzer and tunnel A spring loaded gun on a cart shoots a ball vertically and after the cart passes through a tunnel the ball lands in the barrel.
1D60.10 howitzer and tunnel on air track A launching system for use with an air track cart.
1D60.10 howitzer and tunnel A description of a ball launcher mounted on an air track cart. It can fire a small projectile (1/2" dia.) 10-15 ft.
1D60.10 howitzer and tunnel A car on a track shoots a ball up before it rolls under a tunnel.
1D60.10 howitzer and tunnel A gun mounted on an air puck shoots a ball vertically.
1D60.10 howitzer and tunnel As cart moves at constant velocity a cannon fires a billiard ball vertically. Details in Appendix, p. 545.
1D60.10 howitzer and tunnel Instructor sits on a wheeled cart with a catapult to project a ball upward.
1D60.10 howitzer and tunnel A ball fired vertically from cart moving horizontally falls back into the muzzle.
1D60.10 howitzer and tunnel A steel ball projected upward from a moving car returns into the barrel.
1D60.10 vertical gun on car A ball is shot up from a moving cart and falls back into the barrel.
1D60.15 howitzer and tunnel on incline
1D60.15 howitzer and tunnel on incline
1D60.15 howitzer and tunnel on incline Perform the howitzer and tunnel on an incline with the car starting at rest.
1D60.15 howitzer and tunnel inclined Short note on inclined ballistic cart systems.
1D60.15 howitzer and tunnel on incline Some strobe pictures and drawings show the ball is always above the cart relative to the incline, but not always above the cart relative to the horizontal.
1D60.16 vertical gun on accelerated car
1D60.16 vertical gun on accelerated car Two cases: vertical gun on a car on an incline, and on a car accelerated by a mass on a string.
1D60.20 simultaneous fall Two balls simultaneously dropped and projected horizontally hit the floor together.
1D60.20 simultaneous fall Device to drop one billiard ball and shoot another out.
1D60.20 simultaneous fall A spring loaded device drops one ball and projects the other horizontally.
1D60.20 simultaneous fall Two apparatuses are described for dropping one ball and projecting another.
1D60.20 simultaneous fall One ball is projected horizontally as another is dropped.
1D60.20 shooter/dropper Drop one ball and simultaneously project another horizontally.
1D60.21 simulteanous fall Instructor rolls a superball off the hand while walking at a constant velocity.
1D60.22 simultaneous fall Roll a steel ball down an incline where it hits another, momentum exchange knocks the one out, and the other drops through a slot.
1D60.30 monkey and hunter A gun shoots at a target, released when the gun is fired. The ball hits the target in midair.
1D60.30 monkey and hunter Light beam aiming, air pressure propelled, microswitch to electromagnet release version of monkey and hunter.
1D60.30 monkey and hunter Use a large bore air gun and wood "shell" projectile which is caught in a net.
1D60.30 monkey and hunter A compressed air gun shoots at a tin can.
1D60.30 monkey and hunter Shoot the tin can monkey with a blowgun and an electromagnet release.
1D60.30 monkey gun The apparatus consists of a blow gun with dowel projectile and electromagnetic release.
1D60.31 monkey and hunter on incline A simple and effective version using rolling balls on an inclined table.
1D60.32 monkey and hunter Modifying the Cenco No. 75412 blowgun for bore sighting with a laser.
1D60.32 monkey and hunter A needle valve, reservoir, pressure gauge, and solenoid valve permits varying the muzzle velocity.
1D60.32 monkey and hunter Using the simultaneous fall device to shoot the monkey.
1D60.32 monkey and hunter Shoot the monkey using a rubber band propelled pencil.
1D60.32 monkey and hunter Using a 0.5 L India rubber bulb as a substitute for lungs.
1D60.32 monkey and hunter string resease A simple string release dart gun monkey and hunter.
1D60.32 monkey and hunter A bore sighted blowgun with electromagnetic release.
1D60.33 monkey and hunter Shoot a Christmas tree bulb weighted with a little water.
1D60.33 monkey and hunter Cut out a pop can and cover the hole with paper.
1D60.34 monkey and hunter A magnetic switch and solenoid release.
1D60.34 monkey and hunter A simple switch using infrared optics and a single IC and transistor to release the magnet.
1D60.34 monkey and hunter Bore sighting is used to aim the gun, an optoelectronic device is used to trigger the release. Circuit details are available from the author.
1D60.34 monkey and hunter A photo resistor is used as a switch.
1D60.34 monkey and hunter Use the PSSC cart spring to launch the projectile. Also a simple magnet switch.
1D60.34 monkey and hunter Plotting projectile motion using the OH projector, strobe photography, and an optoelectronic circuit for triggering the monkey drop.
1D60.35 monkey and hunter Viewed from the free monkey frame, the bullet moves uniformly. Placing the hunter below the monkey can mislead students.
1D60.35 monkey and hunter Tutorial
1D60.36 monkey and hunter Investigates the effect of the method of air entry and switch friction on the accuracy of the shot.
1D60.38 monkey and hunter Sound activated electronic flash produces photographic record of the distance the target falls.
1D60.40 range of a gun
1D60.40 range of a gun An air powered cannon (5 psi) shoots a 5 cm dia x 10 cm projectile to better than 1% accuracy.
1D60.40 range of a gun Using the Blackwood ballistic pendulum gun, students are asked to calculate the angle necessary for them to be hit.
1D60.40 range of a gun Shoot at 45, then calculate 30 or 60 and place the target.
1D60.40 range gun Fire a spring loaded gun at various angles.
1D60.42 range of a gun Impact point of a slingshot projectile is predicted from the drawing force and drawing distance.
1D60.43 range of a gun Use the tennis ball serving machine to find muzzle velocity, range, etc.
1D60.44 range of a gun A softball is modified to be fired by the Cenco ballistic pendulum gun (No.75425). Calculate muzzle velocity and examine the range at various angles.
1D60.45 range of a gun Using a toy dart gun and a ball bearing weighted dart, the author gives a concise description for obtaining muzzle velocity used to predict the range at various angles.
1D60.46 range of a gun - gun A toy spring-loaded gun is surprisingly precise.
1D60.46 simple spring gun A spring gun shoots a 3/4" steel ball 12 m/sec with 2% accuracy.
1D60.46 range of a gun - gun On using the Blackwood Pendulum gun as a device for finding the range of a projectile
1D60.46 projectile launcher Making a string and sticky tape launcher out of bamboo.
1D60.46 range of a gun - gun A golf ball fired from a spring powered gun. Construction details in appendix, p. 548.
1D60.46 range of a gun - gun A spring gun for a 3/4" steel ball. Construction details.
1D60.47 range of a projected ball Apparatus Drawings Project No. 32: Plans for a inclined tube for launching a ball.
1D60.50 parabolic path through rings
1D60.50 parabolic path through rings Same as TPT 22(6),402 except the ball is shot with a spring loaded gun.
1D60.50 parabolic trajectory Four launching ramps are mounted to a large magnetic surfaced coordinate system. Magnet based metal hoops can be repositioned easily so the ball passes through all the hoops. Looks very nice.
1D60.50 parabolic path through rings A ball launched off a ramp will pass through a set of rings.
1D60.50 parabolic trajectory Parabolic Lucite templates coincide with path of steel balls projected horizontally.
1D60.50 parabolic trajectory Throw a piece of chalk so it follows a parabolic path drawn on the board.
1D60.55 parabolic trajectory on incline
1D60.55 projectile range on a inclined plane An old, simple, elegant (no calculus) solution.
1D60.55 parabolic trajectories on the OH Ink dipped balls are rolled down an incline onto a tilted stage on an overhead projector.
1D60.55 parabolic trajectory on incline A tennis ball covered with chalk dust is rolled across a tilted blackboard.
1D60.55 parabloic trajectory on incline Inked balls are rolled on a transparent tray on the OH proj. Also Compton effect and Rutherford scattering.
1D60.55 parabolic trajectory on incline Fire a ball up an incline and trace the trajectory as it rolls on carbon paper.
1D60.55 air table parabolas Pucks are projected across a tilted air track.
1D60.56 parabolic trajectory A ball launched off a ramp strikes a vertical carbon paper moved repeatedly away and laterally by equal amounts. Unexpectedly, not dependent on g.
1D60.56 parabolic trajectory Inexpensive apparatus for plotting parabolic trajectory by repeatedly hitting a carbon paper.
1D60.58 parabolic trajectory A strobe picture is taken of the projectile motion of a golf ball. A method of analysis suited for a HS class is presented.
1D60.58 photographing parabolic trajectories Photograph a bouncing ping pong ball through a motorized slotted disc.
1D60.59 falling body simulator An analog computer simulator for falling bodies projected horizontally.
1D60.59 parabolic trajectory Use an analog computer to calculate trajectories.
1D60.60 parabolic trajectory
1D60.60 parabolic trajectory A pivoted bar with several pendula of length proportional to the square of the distance point from the pivot.
1D60.60 parabolic trajectory Uses the balls hanging from a stick device at the blackboard.
1D60.60 parabolic trajectory A pivoted bar has pendula of length proportional to the square of the distance from the pivot point.
1D60.60 parabolic trajectory A stream of water matches the position of balls of lengths 1,4,9,16,... at all angles of elevation.
1D60.61 parabolic trajectory - water stream Apparatus Drawings Project No.33: The adjustable water nozzle has an arm extending in the direction of the nozzle with hanging arrows at intervals along the arm. Adjust the water pressure so the stream matches the arrow heads.
1D60.65 water stream trajectory
1D60.65 water trough trajectory Hook a nozzle to the house water through an additional regulator to reduce pressure fluctuations. Shoot at varying angles into a water trough.
1D60.65 parabolic trajectory A hose aimed with a protractor demonstrates range.
1D60.65 spitting trajectory A pulsar spits out regularly spaced water drops which are viewed with a strobe. A horizontal mirror shows uniform velocity and a vertical mirror shows acceleration.
1D60.65 parabloic trajectory Project light down a horizontally discharged water stream to make the path visible.
1D60.65 spitting trajectory Use a tuning fork to break a stream of water directed at 45 degrees into regularly spaced drops.
1D60.65 spitting trajectory A horizontally projected water jet illuminated with a strobe.
1D60.68 water drop stream Design for a water drop generator based on a speaker driven diaphragm.
1D60.68 water drop stream A vibrator is used to break a horizontally projected stream of water into uniform drops.
1D60.70 dropping the bomb A mechanism to drop a bomb in slow motion from a model airplane.
1D60.71 juggling Juggling higher trajectories requires slower hand motion.
1D60.90 projectiles with analog computer A simple analog computer is used to generate voltages representing the various parameters which are displayed on an oscilloscope.
1D65.15 howitzer and tunnel on incline Prop up one end of the howitzer and tunnel track and start the cart from either end.

1E RELATIVE MOTION

10. Moving Reference Frames

1E10.10 crossing the river
1E10.10 crossing the river Pull a sheet of wrapping paper along the lecture bench while a toy wind up tractor crosses the paper.
1E10.10 crossing the river A long sheet of paper (river) is pulled along the table by winding on a motorized shaft. A motorized boat is set to cross the river. Marking pens trace the paths.
1E10.10 crossing the river A wind up toy is placed on a sheet of cardboard that is pulled along the table.
1E10.10 crossing the river A small mechanical toy moves across a rug which is pulled down the lecture table.
1E10.10 bull dozer on moving sheet (2D) The bulldozer moves across a sheet moving at half the speed of the bulldozer or at the same speed.
1E10.11 toy tractor drive On using toy tractors in kinematics demonstrations.
1E10.15 moving blackboard Using a large movable reference frame on wheels and a walking student, equations of relative speed can be deduced by non science majors.
1E10.20 Frames of Reference film
1E10.20 Frames of Reference film The classic film available on video disc permits use of selective parts.
1E10.22 photographing relative velocity Toy bulldozers, blinkies, and a camera give a photographic record of relative velocities.
1E10.23 Galilean relativity A Polaroid camera and blinky, each on a cart pushed by a toy caterpillar, show the various cases of relative motion.
1E10.31 stick on the caterpiller A small stick placed on the top tread of a toy caterpillar moves twice as fast as the toy.
1E10.41 inertial reference frames Two X-Y axes, one on a moving cart, and "cord" vectors are painted with fluorescent paint and viewed in black light.
1E10.41 inertial reference frames Complicated. Look it up.

20. Rotating Reference Frames

1E20.10 Foucault pendulum
1E20.10 Foucault pendulum A ceiling mounted pendulum swings freely. The change in path is noted at the end of the class period.
1E20.10 Foucault pendulum Suspension for a large (120# - 36') non driven Foucault pendulum.
1E20.10 Foucault pendulum A large pendulum hung from the ceiling swings for an hour.
1E20.10 Foucault pendulum Optical arrangement for projecting the Foucault pendulum motion.
1E20.10 Foucault pendulum Permanent corridor demonstration as described in Scientific American, vol 210, Feb. 64, 132-9.
1E20.10 Foucault pendulum Look at the plane of swing at six ten minute intervals.
1E20.11 short Foucault pendulum Pictures and a circuit diagram for a well done short Foucault pendulum.
1E20.11 short Foucault pendulum A 70 cm pendulum with a method of nullifying the precession due to ellipicity.
1E20.11 Foucault pendulum A Foucault pendulum driver for limited space exhibits.
1E20.11 short, continuous Foucault pendulum Modification of the AJP 46,384 (1978) pendulum to make it portable so it can be moved into lecture rooms for demonstration.
1E20.11 Foucault pendulum Plans for a very short (50 cm) Foucault pendulum.
1E20.11 Foucault pendulum Several novel features that can be incorporated in the design of a short Foucault pendulum to make construction and operation relatively simple.
1E20.12 time lapse Foucault cycle The author will provide a videotape of a complete time lapsed cycle of the Foucault pendulum filmed at the Center of Science and Industry in Columbus for preview and copying.
1E20.13 Foucault pendulum A 2 meter Foucault pendulum with a Charron ring drive.
1E20.14 Foucault pendulum The support wire for a 2.8 meter Foucault pendulum is lengthened by heating at the end of each swing.
1E20.14 Foucault pendulum Foucault pendulum drive mechanisms.
1E20.15 Foucault pendulum drive An electromagnet is placed below the equilibrium position of the bob. Circuit for the drive is given.
1E20.16 Foucault pendulum An optical projection system to show the deflection of a Foucault pendulum after 100 oscillations.
1E20.16 Foucault pendulum General text about the Foucault pendulum.
1E20.19 Foucault pendulum - Onnes experiment A review of Onnes' analysis that led to the first properly functioning Foucault pendulum. More stuff.
1E20.19 general and historical article Some discussion of a current murder novel, some history of Foucault's work, etc.
1E20.20 Foucault pendulum model
1E20.20 Foucault pendulum model A pendulum is mounted on a rotating turntable.
1E20.20 Foucault pendulum model, etc Build a simple model of the Foucault pendulum and demonstrate the Coriolis effect by the curved trace method.
1E20.20 Foucault pendulum model A simple pendulum supported above the center of a turntable.
1E20.20 Foucault pendulum model A simple pendulum hanging from a rotating platform.
1E20.20 Foucault pendulum model Picture of a nice Foucault pendulum model.
1E20.21 rotating frame A monkey puppet sits on a rotating reference frame to help the student visualize a non-inertial frame.
1E20.22 Foucault pendulum model Sit on a rotating chair with a table on your lab. A pendulum releasing ink marks a clear pattern on the paper.
1E20.26 geometric model A geometrical model helps correct some common misconceptions about the plane of oscillation of the Foucault pendulum.
1E20.27 Foucault pendulum Excellent diagram explaining the variation of rotation of the Foucault pendulum with latitude
1E20.28 Foucault pendulum precession Derivation of the Foucault pendulum period shows that no correction factor is needed for (1 m) lengths. Contradicts C.L.Strong, Sci.Am. 210,136 (1964).
1E20.30 Foucault pendulum latitude model
1E20.30 Foucault pendulum latitude model See AJP 47(4),365.
1E20.30 Foucault pendulum latitude model A vibrating elastic steel wire pendulum demonstrates how the rotation of the plane of oscillation depends on the latitude.
1E20.35 Foucault pendulum latitude model A ball on rod pendulum set at 45 degrees latitude can be driven by a solenoid inside the globe.
1E20.35 Foucault pendulum model An electromagnet inside a globe drives a small pendulum at a selected latitude. Construction details p.592.
1E20.40 Theory and two demostrations The concept of a locally inertial frame is used to study motion in accelerated frames. Two demonstrations are presented.
1E20.50 rotating room
1E20.50 rotating room Design for a rotating room that seats four at a table, and has four possible speeds.
1E20.50 motion room A rotating motion room that holds four students.
1E20.50 catch on a rotating platform Students try to play catch on a large rotating system. Other possibilities for the apparatus are discussed.
1E20.51 rotating coordinate frame visualizer Experiments performed on a rotating frame are projected onto a screen through a rotating dove prism. Centrifugal force, coriolis force, angular acceleration, cyclones and anticyclones, Foucault pendulum, etc.

30. Coriolis Effect

1E30.10 draw the coriolis curve - vertical
1E30.10 draw the coriolis curve - vertical Mount a rotating disk vertically, drive a pen on a cart at constant velocity in front of the disk. The speeds of the disk and cart are variable.
1E30.11 draw the coriolis curve
1E30.11 draw the coriolis curve Place a poster board circle on a turntable move a magic marker across in a straight line.
1E30.11 draw the curve Move a magic marker in a straight line across a rotating disc.
1E30.11 draw the curve A cart on a track with a marker passes in front of and draws on a large disc that can be rotated.
1E30.12 coriolis ink drop letter AJP 50(4),381 should have referenced AJP 27(6),429.
1E30.12 coriolis Turn a nearly vertical sheet as a drop of ink is running down it.
1E30.13 coriolis overhead transparency
1E30.13 coriolis overhead transparency Same as AJP 46(7),759.
1E30.13 coriolis machine A clear plastic disk is placed over a inertial reference frame marked with a constant velocity path. Draw marks on the plastic disk while turning through equal angles.
1E30.14 coriolis spark trace The PSSC air puck is used to give a spark trace on a rotating table.
1E30.20 coriolis gun
1E30.20 coriolis gun Same as Mb-25.
1E30.20 coriolis gun A spring loaded gun at the center of a 4' disc is shot at a target first at rest and then while spinning.
1E30.20 coriolis gun A clamped dart gun is fired by an instructor sitting on a revolving chair into a target board.
1E30.20 coriolis gun A spring gun at the center of a rotating table fires into a target at the edge.
1E30.21 coriolis Go to a merry-go-round and walk on it. You will feel a very strange "force".
1E30.24 spinning Coriolis globe A ball on a string is threaded through the pole of a spinning globe. Pull on the string and the ball moves to higher latitudes and crosses the latitude lines.
1E30.26 coriolis dish and TV A ball oscillates in a spherical dish at rest, and follows various curved paths when the dish is rotated at different speeds. A TV camera is mounted to the rotating frame. More.
1E30.27 coriolis rotating platform and tv A puck is launched on a rotating platform and the motion is followed with a TV
1E30.28 coriolis ball on turntable
1E30.28 Coriolis effect Roll a ball across a slowly rotating turntable.
1E30.30 leaky bucket on turntable A can with a hole is mounted above a rotating table. As the table turns, the stream of water is deflected.
1E30.32 drop ball on turntable A mass falls on a disc first while it is rotating and then when it is stationary. Difference in point of impact is noted.
1E30.33 coriolis trajectory A ball describing an arc is released first in a stationary coordination system and then in a rotating system.
1E30.34 coriolis water table A flat board rotates in a horizontal plane with a flexible tube full of flowing water running lengthwise. The tube deflects upon rotation.
1E30.34 coriolis water table A flexible rubber tube with water flowing in it is stretched across a disc which can be rotated. The tube deflects when rotated.
1E30.34 coriolis water table A flexible rubber tube with water flowing in it is stretched across a disc which can be rotated. The tube deflects.
1E30.35 rotating water flow table Food coloring used to mark flow is introduced at the edges of a circular rotating tank with a center drain hole. A rotating overhead TV camera allows motion in the rotating frame to be viewed.
1E30.36 coriolis A pan of water on a turntable has a recirculating pump with an inlet and exit of opposite sides of the pan. Floats above these areas rotate in opposite directions as the pan of water is spun.
1E30.50 rotating TV camera
1E30.50 rotation table with tv
1E30.51 rotating TV camera A TV camera is rotated in front of an oscilloscope displaying a slow ellipse. Vary the camera rotation.
1E30.61 vacuum cleaner Cover the exhaust of an old vacuum: the current decreases as the RPM increases. Demonstrates transformation of vectors from a moving coordinate system to a rest frame. In one frame the torque does no work, in the other with open exhaust torque is responsible for the entire power.
1E30.71 spinning dancer - coriolis analysis The spinning dancer, usually treated as an angular momentum problem, is used as a coriolis example.

1F NEWTON'S FIRST LAW

10. Measuring Inertia

1F10.10 inertia balance A torsion pendulum has cups that can be loaded with various masses.
1F10.10 inertia balance A light torsion pendulum can be loaded with various masses.
1F10.10 inertia balance Torsion pendulum as an inertia balance.
1F10.11 inertia balance - leaf spring
1F10.11 inertia balance A horizontal leaf spring as an inertial balance.
1F10.11 inertia balance Place masses on a platform supported by horizontal leaf springs.
1F10.12 inertia oscillation A puck between two springs rolling on Dylite beads is timed with several different masses.
1F10.13 inertial equal arm balance Publication of an unfinished demonstration, but up front about it. Shows circuit diagram for a indicator for a horizontal Roberval type balance on an acceleration cart.
1F10.13 inertia balance Measure the period of a commercially available (?) inertia balance by using a stroboscope.
1F10.20 inertia bongs
1F10.20 inertia bongs Hit hanging 2"x4"x10" blocks of wood and steel with a hammer.
1F10.20 inertia bongs Two large cylinders are suspended, one wood (3Kg) and one iron (50Kg). Students compare displacements when struck by a hammer or just push the things around.
1F10.25 foam rocks
1F10.25 foam rocks Hit a real rock (granite) then a foam rock (looks like granite) with a hammer. Throw a form rock at some students.
1F10.25 foam rock Hit a real rock and then a foam rock with a heavy mallet.
1F10.30 judging inertial mass A blindfolded volunteer compares a mass on a string with a mass on a roller cart.

20. Inertia of Rest

1F20.10 inertia balls Break the string on the top or bottom of a suspended mass.
1F20.10 inertia balls Two heavy iron balls are hung separately between lengths of string. Pull on one and jerk on the other.
1F20.10 inertia balls Two steel balls are suspended by strings with identical strings tied from their bottoms. Give a quick jerk to one and pull the other slowly.
1F20.10 inertial balls Break the string on the top or bottom of a suspended mass.
1F20.10 inertia ball A mass is suspended between two cords. Pull slowly or jerk on the lower cord.
1F20.11 bowling ball inertia balls
1F20.11 bowling ball inertia balls Replace the standard 6 cm balls with bowling balls for increased visibility.
1F20.12 inertia balls One mass is hung from a string and another mass hung below it. Jerk the lower mass to break one of the strings.
1F20.13 inertia stick A long stick is supported from rings of filter paper at each end. Break the filter paper with a pull or the stick with a jerk.
1F20.15 inertia block
1F20.15 inertia block A 50 lb mass is mounted on rollers. A thread will pull it but a rope can be broken with a jerk.
1F20.16 inertia block Tie a loop of 7/16" braided cotton cord through a hole in a 2"x4"x10" steel block. Pull and jerk with a hammer.
1F20.16 inertia block A length of rope is tied to a 10 lb. block. A pull with a hammer will move the block but a jerk will break the rope.
1F20.16 inertia block A rope is attached between a heavy iron ball and a hammer head. A fast swing of the hammer takes up the slack and breaks the rope without moving the ball.
1F20.18 inertia balls - analysis For the more advanced reader. The system may be treated as a forced harmonic oscillator and the classical results of the demonstration are verified analytically. Surprises emerge.
1F20.20 smash your hand
1F20.20 smash your hand Place a lead block on your hand and hit it with a hammer.
1F20.20 smash your hand Hit a 10 lb. brick with a hammer while it rests on your hand.
1F20.21 smash your hand, etc. Hit a 10 lb block on the hand or a 50 lb brick on the stomach with a hammer. Pound nails into a 50-75 lb wood block placed on a student's head.
1F20.22 hit the nail on the head
1F20.22 hit the nail on the head Place a physics book, then a 6"x6" block of wood on a student's head and drive a nail into the block.
1F20.22 hit the nail on the "head" Drive a nail into a large block of wood placed on a student's head.
1F20.25 smash block on bed of nails
1F20.25 smash the block An analysis of smashing a block on a volunteer sandwiched between two nail beds. Safety issues are discussed.
1F20.25 smash the block A bed of nails is placed on the chest before smashing the block with a sledge.
1F20.26 vibrograph An optical lever arrangement for magnifying small displacements of a large mass when the table is hit with a hammer.
1F20.30 tablecloth pull
1F20.30 tablecloth pull
1F20.30 the tablecloth pull Pictures and a few hints.
1F20.30 tablecloth pull Pull the tablecloth out from under a place setting.
1F20.30 tablecloth pull Pull a low friction tablecloth from under a place setting.
1F20.33 inertia cylinder
1F20.33 inertia cylinder Stand a 3/4" x 6" aluminum cylinder on a sheet of paper. Jerk the paper out from under the cylinder.
1F20.33 inertia cylinder Jerk a sheet of paper out from under a thin steel cylinder.
1F20.34 coin/card snap
1F20.34 card/coin snap Snap a card out from under a tall object, e.g., a shipping tag from under a balanced claw hammer.
1F20.34 card/coin snap Several inertia tricks.
1F20.34 card/coin snap Snap a piece of cardboard from under a steel ball.
1F20.35 eggs and pizza pan
1F20.35 eggs and pizza pan Set a pizza pan on three 2l beakers full of water, stand paper cylinders with eggs at the tops above the beakers, knock out the pizza pan.
1F20.35 blocks and broomstick Egg on a spool, on a pie tin, on a beaker of water. Flex broom and knock out pie tin.
1F20.35 eggs and pizza pan Place a pizza pan on three beakers, place cardboard tubes on the pan directly above the beakers, and eggs on the tubes. Knock out the pizza pan.
1F20.36 pin and embroidery hoop
1F20.36 pin and embroidery hoop
1F20.40 stick on wine glasses
1F20.40 stick on wine glasses Stick needles in the ends of a 3/4" sq x 4' clear pine bar. Place the needles on wine glasses full of water and break the stick with an iron bar.
1F20.50 shifted air track inertia
1F20.50 shifted air track inertia Support an air track on wheels. Move the air track under an air glider.
1F20.50 shifted air track inertia Move the air track under an air track glider.
1F20.60 loose hammer head A hammer handle may be tightened by pounding on the far end of the handle.
1F20.61 inertia cart A cart has a pivoting arm with different masses but the same volume at the ends. The greater mass lags behind as the cart is accelerated.
1F20.62 string of weights A string of weights connected by springs shows uneven deformation when jerked.
1F20.64 inertia of liquids There are two horizontal glass tubes, one with a cork cylinder and the other with a lead cylinder. Strike the stopper at one end of the glass tubes with a hammer and watch the direction of the cylinders.

30. Inertia of Motion

1F30.10 persistence of motion (air track) A single cart on the air track.
1F30.10 persistence of motion (air track) A single cart on the air track.
1F30.11 air table puck Air table with a puck.
1F30.13 CO2 block A large piece of dry ice on a flat formica top wetted with alcohol.
1F30.21 water hammer
1F30.21 water hammer Some water in an evacuated test tube clicks when the water hits the end of the tube.
1F30.21 water hammer Shut off the sink faucet and a water hammer may be heard. A small tube evacuated with some water shows the effect nicely.
1F30.21 water hammer A tube is evacuated except for some water. When the tube is stopped suddenly, the water strikes the end of the tube with a click.
1F30.21 water hammer Evacuate a glass tube containing water.
1F30.30 car on cart on cart
1F30.30 car on cart on cart A small car on a skateboard on a large roller cart hits a stop level with the roller cart and the skateboard and car continue to move at constant velocity.
1F30.30 cart on a cart A smaller roller cart is placed on a larger one. when the larger is stopped, the smaller continues.
1F30.40 nail by hand
1F30.40 nail by hand Follow the directions in TPT 18(1),50.
1F30.40 hand pile driver Drive a nail into wood with your bare hands.
1F30.50 pencil and plywood
1F30.50 pencil and plywood Place a pencil in a brass tube hooked to a fire extinguisher. Fire the pencil into a 1/2" plywood board.
1F30.50 pencil and plywood Use a CO2 extinguisher to fire a pencil through a 1/2" plywood.

1G NEWTON'S SECOND LAW

10. Force, Mass, and Acceleration

1G10.10 glider, mass, and pulley on air track
1G10.10 acceleration air glider Air track cart pulled by a falling weight.
1G10.10 acceleration air glider Accelerate a car on a track with a mass on a string over a pulley.
1G10.10 glider, mass, and pulley An air track cart is timed while pulled by a mass on a string over a pulley.
1G10.10 string and weight acceleration (air Three cases of an air glider pulled by a falling weight.
1G10.11 constant mass acceleration system
1G10.11 constant mass acceleration system A cart on the air track is accelerated by a mass on a string over a pulley and final velocity timed photoelectrically. Keep the mass of the system constant by transferring from the cart to the pan.
1G10.11 acceleration air glider Air cart with a string over a pulley to a mass. Vary mass on both cart and hanger.
1G10.12 acceleration air glider on incline An puck is timed as it floats up an incline pulled by a string to a weight over a pulley.
1G10.13 acceleration air glider on incline An air track cart is accelerated up an inclined track by the string, pulley and mass system. A newton scale is included on the cart to measure the tension in the string directly. An electromagnet release and photogate timer at a fixed distance are used to derive acceleration.
1G10.14 acceleration glider accelerometer An elegant pendulum accelerometer designed for the air track. Reflected laser beam is directed to a scale at one end of the track.
1G10.15 roller cart and bunge loop
1G10.15 roller cart and bunge loop
1G10.16 Strang gage
1G10.16 acceleration with spring (airtrack) An air track glider is pulled by a small spring hand held at constant extension.
1G10.17 constant force generators A note that picks some nits about the hanging mass, mentions the "Neg'ator" spring.
1G10.18 battery propeller force generator Plans for a battery powered air track propeller that provides a constant force.
1G10.19 constant force generator A constant force generator for the air track based on the induction of eddy currents. It is easy to handle and can be self-made.
1G10.20 accelerated car
1G10.20 accelerated instructor
1G10.20 acceleration car Time the acceleration of a toy truck as it is pulled across the table by a mass on a string over a pulley.
1G10.21 acceleration car and track Apparatus Drawings Project No. 15: Large low friction acceleration carts and track for use in the lecture demonstration.
1G10.21 acceleration car Three different pulley arrangements allow a cart to be accelerated across the table top.
1G10.21 acceleration car A car is accelerated by a descending weight.
1G10.21 acceleration car, mass & pulley Distance and time are measured as a toy truck is accelerated by a mass and pulley system.
1G10.22 accelerated instructor
1G10.24 acceleration car photo Take a strobed photo of a light on a car pulled by a weight on a string over a pulley.
1G10.25 acceleration block
1G10.25 acceleration block Accelerate a block of wood across the table by a mass on a string over a pulley.
1G10.26 acceleration car A complex arrangement to accelerate a car, vary parameters, and graph results is shown. Details in appendix, p.549.
1G10.30 mass on a scale
1G10.30 weight of a mass Suspend a mass from a spring balance and then cut the string.
1G10.30 mass on a scale Hang a mass on a spring scale to show reaction of the scale to mg.
1G10.40 Atwood's machine Two equal masses are hung from a light pulley. A small percentage of one mass is moved to the other side.
1G10.40 Atwood's machine Place 1 kg on each side of a light pulley on good bearings. Add 2 g to one side.
1G10.40 Atwood's machine Three skeletonized aluminum pulleys are mounted together on good bearings. Many combinations of weights may be tried.
1G10.40 Atwood's machine Two equal masses are hung from a light pulley. A small percentage of one mass is moved to the other side.
1G10.40 Atwood's machine An Atwood's machine using an air pulley.
1G10.40 Atwood's machine The small weight is removed after a period of acceleration and the resulting constant velocity is measured.
1G10.42 Atwood's machine Hang the weights from spring balances on each side.
1G10.44 Atwood's machine A rotation free Atwood's machine using air bearing surface and spark timer.
1G10.44 Atwood's machine Atwood's machine using an air bearing and spark timer.
1G10.45 Atwood's machine problem One of the best nerd problems ever.
1G10.45 Morin's machine Morin's (French) alternative to Atwood's (English) machine.
1G10.51 auto acceleration On using automotive magazine test results to study kinematic relations.
1G10.52 car time trials Use student's cars to do time trials in the school parking lot.

20. Accelerated Reference Frames

1G20.10 candle in a bottle
1G20.10 candle in a bottle Drop a candle burning in a large flask.
1G20.10 candle in a bottle Drop, toss up, and throw a bottle containing a lighted candle.
1G20.10 gravitational pressure in circulatio Drop a plexiglass container with a lighted candle.
1G20.10 bottle and candle Throw a jug with a lighted candle into the air.
1G20.10 candle in a bottle A lighted candle in a glass chimney in a large container will burn for a long time unless dropped.
1G20.10 candle in a bottle A candle in a dropped chimney goes out after 2-3 meters due to absence of convection currents.
1G20.10 candle in dropped jar Drop a closed jar containing a burning candle.
1G20.11 falling candle doesn't work Hey, when these guys tried it they could drop the bottle 25 feet and the candle only went out upon deceleration.
1G20.13 elevator paradox A large hydrometer flask in a beaker of water remains at its equilibrium position as the beaker is moved up and down.
1G20.14 four demos Four demos: Drop a weight on a spring balance, drop a cup with weights on rubber bands, drop a candle in a bottle, drop or throw a tube of water containing a rising cork.
1G20.20 ball in a thrown tube
1G20.20 ball in a thrown tube Invert and throw a 4' plexiglass tube full of water that contains a cork. The rising cork will remain stationary during the throw.
1G20.20 ball in a thrown tube Throw or drop long water filled tube containing a cork. Also try a rubber stopper or air bubble.
1G20.20 falling bubble A rising bubble in a jar remains stationary while the jar is thrown.
1G20.20 ball in a thrown tube A long thin tube with an air bubble is tossed across the room.
1G20.21 modified falling tube Couple a lead weight and cork with a spring and put the assembly in a tube of water so the cork just floats. Drop the tube and the cork sinks.
1G20.21 ball in a falling tube A cork remains submerged in a falling jar of water. Diagram of a mousetrap mechanism.
1G20.22 ball in a falling tube A ball and tube are dropped simultaneously from the ceiling. The ball strikes the bottom of the tube after hitting the floor.
1G20.30 leaky pail drop
1G20.30 drop pail with holes First drop a can with several vertical holes to show no flow in free fall, then rig up a pulley system to accelerate the pail greater than g (shown), and the top hole will issue the longest stream of water.
1G20.30 leaky pail drop Punch a hole in the bottom of a can and fill it with water. When you drop it, no water will run out.
1G20.33 pop the balloon This device pops a balloon if it is not in free fall. Toss it to a student to give them a real bang.
1G20.34 vanishing weight A strip of paper pulled from between two weights will tear except when dropped.
1G20.36 vanishing weight Weights compress the tube of an air whistle until in free fall when the whistle blows.
1G20.38 Einstein's birthday present A ball attached to a tube by a weak rubber band is pulled to the tube in free fall.
1G20.40 cup and weights
1G20.40 cup and weights Hang 1 kg weights from heavy rubber bands extending from the center over the edge of a styrofoam bucket. Drop the thing.
1G20.40 cup & weights Further discussion of the R. D. Edge article describing dropping a styrofoam cup with weights suspended over the edge by rubber bands.
1G20.41 vanishing weight - dropping things 1) Drop a mass on a spring scale, 2) Drop an object with a second object hanging by a rubber band, 3) stretch a rubber band over the edge of a container and drop.
1G20.42 vanishing weight A parcel scale is dropped with a bag of sand on the platform.
1G20.43 elevators A battery powered circuit is constructed in a box causes a light to glow while a spring scale is unloaded. The light will glow while a loaded spring scale is in free fall.
1G20.44 drop a mass on a spring Drop a frame with an oscillating mass on a spring and the mass will be pulled up but stop oscillating.
1G20.45 dropped slinky
1G20.45 dropped slinky
1G20.45 dropped slinky Hold a slinky so some of it extends downward, then drop it to show the contraction.
1G20.46 vanishing weight Drop a frame containing three different masses hanging on identical springs or a frame with a pendulum.
1G20.47 dropping pendulum Suspend a pendulum from a stick. Drop the stick when the pendulum is at an extreme and the stick and pendulum will maintain the same relative position.
1G20.55 falling frame shoot A falling cage is equipped with two guns lined up with holes in two sheets and a net to catch the ball. The balls don't go through the holes unless the cage is in free fall.
1G20.60 elevators Quickly raise and lower a spring balance-mass system.
1G20.61 elevators Discussion of the elevator problem and a car going around a curve.
1G20.62 elevators A rope over a ceiling mounted pulley has a weight on one side and a spring scale and lighter weight on the other side.
1G20.63 elevators An apparatus to quantitatively demonstrate the forces acting on a passenger standing on a spring scale in an elevator. Diagrams.
1G20.64 elevator The elevator is a spring scale and potentiometer combination.
1G20.70 local vertical with acceleration
1G20.70 accelerometer on tilted air track The water surface of a liquid accelerometer on a tilted air track remains parallel to the angle of the air track during acceleration.
1G20.70 showing acceleration Put a cart on an incline, mount a liquid accelerometer on the cart and mark the reference at rest, give the cart a push up the incline and observe the accelerometer as the car goes up, stops, and comes back down.
1G20.70 accelerometer A Lucite box containing colored glycerine mounted on a cart is rolled down an incline or given a push up an incline.
1G20.70 local vertical with acceleration Place a liquid accelerometer on an air track glider on an inclined air track
1G20.75 helium balloon accelerometer Put two students in a car with a helium balloon.
1G20.75 accelerometer A balloon filled with air is suspended from the top and a helium balloon from the bottom of a clear box mounted on wheels.
1G20.76 suspended ball accelerometers
1G20.76 float accelerometer A float in a glass of water on an accelerating cart. Also, moving in uniform circular motion.
1G20.76 accelerometer Two flasks full of water, one has a cork ball, the other has a heavier than water ball.
1G20.76 accelerometer An iron ball is suspended from the top and a cork ball from the bottom of a clear box filled with water mounted on wheels.
1G20.76 accelerometers Two jars of water, one has a light ball suspended from the bottom, the other has a heavy ball suspended from the top.
1G20.79 accelerometer A design for a high quality accelerometer.
1G20.80 cart and elastic band
1G20.80 cart and elastic band Place an accelerometer (cork on a string in a clear water filled box) on a cart and attach a strong rubber band to one end. Push the cart down the bench while holding the rubber band.
1G20.85 acceleration pendulum cart
1G20.85 acceleration pendulum cart Push a skateboard across the lecture bench so an attached pendulum is displaced at a constant angle.
1G20.87 accelerometer The bubble of a spirit level moves in the direction of acceleration.
1G20.87 accelerometer Place a carpenter's level on Fletcher's trolley and use the bubble as an accelerometer.
1G20.88 accelerometer A discussion of "U" tube manometers for use as accelerometers.

30. Complex Systems

1G30.11 Poggendorff's experiment The reaction on an Atwood's pulley hanging from a scale is twice the harmonic mean of the suspended weights.
1G30.11 tension in Atwood's machine Hang an Atwood's machine from a spring scale and take readings in both static and dynamic cases.
1G30.12 double Atwood's machine problem The mass on one side of the Atwood's machine is replaced with another Atwood's machine.
1G30.20 mass on spring, on balance
1G30.20 mass on spring, on balance A mass on a spring oscillates on one side of a tared balance.
1G30.20 mass on a spring, on balance A large ball on a stretched spring is tared on a platform balance. The string is burned and the motion observed.
1G30.20 acceleration on a balance Burn the string extending a mass on a spring on a tared platform balance.
1G30.25 weigh a yo-yo A yo-yo is hung from one side of a balanced critically damped platform scale.
1G30.30 hourglass on a balance
1G30.30 hourglass on a balance An hourglass runs down on a tared, critically damped balance.
1G30.30 acceleration of center of mass A very large hourglass is placed on a critically damped balance. The deflection is noted as the sand starts, continues, and stops falling.
1G30.30 acceleration of center of mass An hourglass full of lead shot is tared on a critically damped platform balance. The resultant force is observed as the lead shot starts, continues, and stops falling.
1G30.30 hourglass on a balance An hourglass on one side of a equal arm balance.
1G30.31 acceleration of center of mass An apparatus to show transient and steady state conditions in the hourglass problem.
1G30.32 the hourglass problem Careful analysis and demonstration shows that the center of mass is actually accelerating upwards during most of the process.
1G30.33 acceleration of center of mass A funnel full of water is placed on a tared platform balance and the water is then released and runs into a beaker.
1G30.34 reaction balance One mass on an equal arm balance is supported by pulleys at the end and fulcrum. The balance is in equilibrium if the string holding the mass is held fast or pulled in uniform motion. Look it up.
1G30.35 acceleration of center of mass A ball is dropped in a tall cylinder filled with oil while the entire assembly is on a balance. A hollow iron ball may be released from an electromagnet on the bottom and float to the top.

1H NEWTON'S THIRD LAW

10. Action and Reaction

1H10.01 action and reaction see 1N20.
1H10.10 push me pull me carts Two people stand on roller carts and both pull on a rope or push with a long stick.
1H10.10 push me pull me carts Two people stand on roller carts and both pull on a rope. A long stick may be substituted to allow pushing.
1H10.10 rope and carts People on two identical roller carts pull each other with a long rope.
1H10.11 rope and carts All the things you can do standing and running on carts with and without ropes.
1H10.12 rope and carts Stand on a cart holding a rope passing over a pulley to a weight slightly less than static friction, then pull the rope.
1H10.15 reaction air gliders
1H10.15 reaction gliders Burn a string holding a compressed spring between two air gliders.
1H10.20 Newton's sailboat
1H10.20 Newton's sailboat Propel an air glider with a battery powered fan, then attach a sail directly in front of the fan.
1H10.20 Newton's sailboat A battery powered fan and sail can be mounted on a air track cart. Three cases are demonstrated: 1) sail attached, fan not attached; 2) both sail and fan attached; 3) fan attached, no sail.
1H10.20 fan car with sail A sail is placed in front of a battery powered fan on a cart.
1H10.21 Newton's sailboat A balloon provides an air source on one cart, a sail is mounted on another cart. Hold each stationary in turn.
1H10.25 heilicopter rotor
1H10.25 helicopter rotor A symmetric propeller deflects air down, causing upward lift.
1H10.30 cannon car A small brass cannon mounted on one car fires a bullet into a wood block on another of equal mass. A string tying the carts together will result in no motion.

11. Recoil

1H11.01 recoil see 1N20
1H11.10 floor cart and medicine ball
1H11.10 floor cart and medicine ball Stand on a roller cart and throw a medicine ball or styrofoam ball.
1H11.10 floor cart and medicine ball Throw a heavy medicine ball while standing on a roller cart.
1H11.11 stool on conveyor
1H11.11 stool on a conveyor Throw a ball while on a stool mounted on a conveyor.
1H11.20 tennis ball cannon A cannon on wheels shoots a tennis ball.
1H11.20 tennis ball cannon
1H11.30 liquid nitrogen cannon
1H11.30 liquid nitrogen cannon A liquid nitrogen powered cannon on wheels shoots heavy and light stoppers.
1H11.30 liquid nitrogen cannon A cork is shot out of a liquid nitrogen cannon.
1H11.30 liquid nitrogen cannon CO2 provides the pressure to blow a cork out of a cannon on wheels.
1H11.30 liquid air gun Liquid air in a bent test tube shoots a cork when the escape valve is closed.
1H11.40 ballistic gun Shoot a spring loaded bifilar suspended gun. Measure the muzzle velocity by range and the recoil by adjacent scale.
1H11.41 open cannon A hole in the back of a rail mounted gun allows the gasses to escape or not to show the difference on recoil.
1H11.44 bent gun A spring loaded gun firing a steel ball has a barrel bent 90 degrees to show recoil opposite the exit direction instead of the firing direction.

1J STATICS OF RIGID BODIES

10. Finding Center of Gravity

1J10.09 center of gravity Many examples of simple center of mass demonstrations.
1J10.10 map of state Suspend a map of the state from holes drilled at large cities to find the "center of the state".
1J10.10 map of state Sandwich of a map of the state between two plexiglass sheets and suspend from holes drilled at large cities to find the "center of the state".
1J10.10 map of Minnesota A plexiglass map of the state is suspended from several points.
1J10.11 find the center of gravity Use a chalk line on the plumb bob and snap it to make a quick vertical line.
1J10.12 hanging shapes Use the plumb bob method to find the center of gravity of various geometric shapes.
1J10.12 hanging board Suspend an irregular board from several points and use a plumb bob to find the center of gravity.
1J10.12 irregular object center of mass Suspend an irregular object from several points and find the center of mass with a plumb bob.
1J10.15 hanging potato Hang a potato from several positions and stick a pin in at the bottom in each case. All pins point to the center of gravity.
1J10.20 loaded beam - moving scales
1J10.20 meter stick on fingers Slide your fingers together under a meter stick and they meet at the center of gravity. Add a baseball hat to one end and repeat.
1J10.20 friction and pressure Slide your fingers under the meter stick to find the center of mass.
1J10.20 meter stick on fingers Slide your fingers under a meter stick to find the center of mass.
1J10.25 center of gravity of a broom
1J10.25 center of gravity of a broom Bring your fingers together under a broom the find the center of gravity.
1J10.25 center of gravity of a broom Find the center of gravity of a broom, hang a kg mass somewhere on the broom, find the new center of gravity, calculate the weight of the broom by equating torques.
1J10.26 balance beam and bat
1J10.26 balance beam and bat
1J10.30 meter stick on fingers
1J10.30 loaded beam - moving scales Slide the scales together under a loaded beam noting the scale readings of the moving and stationary scales.
1J10.30 loaded beam - moving scales Instead of moving the masses on the beam, move the scales under the beam. Same as bringing your fingers together under the meter stick.
1J10.41 your center of gravity Two methods for measuring the center of gravity of a person are shown.

11. Exceeding Center of Gravity

1J11.10 leaning tower of Pisa
1J11.10 leaning tower of Pisa Add a top to a slanted cylinder and it falls down. Also hang a plumb bob from the center of mass in each case.
1J11.10 leaning tower of Pisa A model of the tower constructed in sections. Adding the top will cause it to tip over.
1J11.10 leaning tower of Pisa Add on to the leaning tower and it falls down.
1J11.10 leaning tower of Pisa The leaning tower of Pisa.
1J11.11 toppling cylinders
1J11.11 falling cylinders A tube, weighted at the bottom, falls when a cap is added. An upright cylinder, containing two balls, falls when a weighted cap is removed.
1J11.11 toppling cylinders The standard leaning tower and an upright cylinder that topples when the cap is removed. It has two balls in the tube.
1J11.12 irregular object center of mass
1J11.15 tipping block on incline
1J11.15 tipping block on incline Raise an incline plane until a block tips over.
1J11.15 tipping block on incline A very clever modification of the leaning tower of Pisa demonstration.
1J11.15 tipping block on incline A block is placed on an incline and the incline is raised until the block tips.
1J11.20 leaning tower of Lire Stack blocks stairstep fashion until the top block sticks out beyond any part of the bottom block.
1J11.20 leaning tower of Lire Use 6"x6"x2' wood blocks and have a student sit under the stack as it is built.
1J11.20 leaning tower of lire A note discussing the derivation of the harmonic series describing the leaning tower of Lire.
1J11.20 leaning tower of Lire Use the center of mass of a composite object to support a block beyond the edge of the lecture bench. This article emphasizes a lab approach. Ref. AJP 23,240 (1955).
1J11.20 leaning tower of Lire Stack blocks until the top block sticks out beyond any part of the bottom block.
1J11.21 cantilevered books The number of books necessary to overhang 2,3,4, etc lengths.
1J11.30 instability in flotation A device to raise the center of mass in a boat until the boat flips. Diagram.
1J11.40 male and female center of gravity
1J11.40 people tasks, etc. Pictures of three center of mass objects and several person based center of mass tasks e.g., stand on your toes facing the wall, etc.
1J11.40 male & female center of gravity Stand with right shoulder and foot against the wall and raise your left foot. Stand with your heels against the floor and try to touch your toes.
1J11.50 double cone
1J11.50 double cone As a double cone moves up an set of inclined rails, its center of gravity lowers.
1J11.50 rolling uphill A simple version of a ball rolling up a "v".
1J11.50 double cone A double cone rolls up an inclined "v" track.
1J11.50 double cone Double cone and rails.
1J11.50 double cone A double cone rolls up an inclined "v" track.
1J11.50 double cone on incline The double cone appears to roll uphill.

20. Stable, Unstab., and Neut. Equi

1J20.10 bowling ball stability
1J20.10 bowling ball stability A bowling ball is placed in, on, and along side a large plexiglass hemisphere.
1J20.11 balance the cone
1J20.11 balance the cone
1J20.11 balance the cone A cone can show stable, unstable, and neutral equilibrium; a sphere shows only neutral equilibrium.
1J20.11 balance the cone A large cone shows stable, unstable, and neutral equilibrium.
1J20.11 stability Balance a cone, show a block is stable and a sphere is neutral.
1J20.12 wood block stability
1J20.12 wood block stability A block and support have marks that show whether the center of gravity has moved up or down when the block is displaced.
1J20.15 block on the cylinder
1J20.15 block on the cylinder A rectangular block of wood is placed on a cylinder first with the width less than the radius (stable) and then with the width greater (unstable).
1J20.15 block on the cylinder An "elementary" discussion of the oscillatory properties of the block on the cylinder.
1J20.15 block on the cylinder A thin block on a cylinder is stable, a thick one is not.
1J20.16 catenary surface A large block is always in stable equilibrium anywhere along this catenary surface.
1J20.17 block on curved surfaces
1J20.17 block on curved surfaces A block is placed on a catenary surface, a circle, and a parabola.
1J20.20 fork, spoon, and match
1J20.20 fork, spoon, and match Place a spoon and match in the tines of a fork and balance the assembly on the edge of a glass.
1J20.20 fork, spoon, and match Picture of the fork, spoon, and match balanced on the edge of a glass.
1J20.20 fork, spoon, and match Stick two forks and a match together and balance on a glass while pouring out the water.
1J20.20 fork, spoon, and match Two forks and a match can be balanced on the edge of a glass while the water is poured out.
1J20.25 nine nails on one
1J20.25 nine nails on one A technique to balance ten landscape spikes on the head of a single upright spike.
1J20.30 sky hook
1J20.30 sky hook A complete solution to the hanging belt problem.
1J20.30 hanging belt Shows a "belt hook" for the hanging belt.
1J20.32 spoon on nose
1J20.32 spoon on nose Hang a spoon on your nose. Most effective with giant food service spoons.
1J20.35 horse and rider
1J20.35 horse and rider A horse has an attached weight to lower the center of mass.
1J20.35 horse and rider Stable equilibrium of a center of gravity object.
1J20.35 horse and rider A horse has a weight attached to lower the center of mass.
1J20.40 balancing man Stable equilibrium of a center of gravity object.
1J20.40 balancing man Stable equilibrium of a center of gravity object.
1J20.45 tightrope walking
1J20.45 tightrope walking Design of a 10' long "low wire" and description of the physical feats possible.
1J20.45 tightrope walking A toy unicycle rider carrying a balancing pole travels along a string.
1J20.45 clown on rope A toy clown rides a unicycle on a wire.
1J20.46 tightrope walking model
1J20.46 tightrope walking model A model of a tightrope walker shows the center of mass moves up with tipping.
1J20.50 balancing a stool Wires form a support at the center of gravity of a lab stool.
1J20.50 balancing a stool Construct a stool so that wires crossed diagonally will intersect at the center of gravity. The stool can be oriented in any direction.
1J20.51 chair on a pedestal
1J20.51 chair on pedestal Hide heavy weights in the ends of a chair's legs so it will balance on a vertical rod placed under the seat.
1J20.55 broom stand
1J20.55 broom stand Spread the bristles and a straw broom will stand upright.
1J20.60 wine butler
1J20.60 wine buttler Stick the neck of a wine bottle through a hole in a slanted board and the whole thing stand up.
1J20.65 glass on coin, etc Pictures show the hanging belt, pin on the point of a needle, and a jar balanced on its edge.

30. Resolution of Forces

1J30.10 suspended block Forces parallel and perpendicular to the plane will support the car midair when the plane is removed.
1J30.10 suspended block A 3-4-5 triangle holding a block. Add counterweights and remove the incline.
1J30.10 suspended block The components of force of a block on an inclined plane are countered by weights. The plane is then removed.
1J30.10 suspended block A 5-6-7 suspended block system is used to show the pulleys can be moved as long as the angle remains constant.
1J30.10 suspended block Forces parallel and perpendicular to the plane will support the car when the plane is removed.
1J30.10 load on removable incline Place a cart on a removable 30 degree incline.
1J30.15 normal force
1J30.15 normal force A block on an incline has an arrow mounted from the center of mass perpendicular to the surface with "N" on the arrowhead and another arrow hanging from the center of mass with a "g" on the arrowhead.
1J30.18 hanging the plank A heavy plank is suspended from three spring scales in several configurations: series, parallel, and a combination.
1J30.20 tension in a string
1J30.20 tension in a string The weight of a mass hung from a single spring scale is compared to the weight shown on a spring scale between two masses over pulleys.
1J30.20 tension in a string A spring scale is suspended between strings running over pulleys to equal weights.
1J30.21 tension in a string A clever story.
1J30.22 tension in a spring Two students pull against each other through one and then two spring scales.
1J30.23 tension in springs Masses are hung at the ends of a series of spring scales.
1J30.25 rope and three students Two large strong students pull on the ends of a rope and a small student pushes down in the middle.
1J30.25 rope and three students Two large strong students pull on the ends of a rope and a small student pushes down in the middle of the rope.
1J30.25 rope and three students Two football players stretch a 10 m rope while a small person pushes the middle to the floor.
1J30.25 clothesline Hang a 5 newton weight from a line and pull on one end of the line with a spring scale.
1J30.26 rope and three weights
1J30.26 rope and three weights Suspend a rope over two pulleys with masses on the ends and hang another mass from the center. Measure the deflection.
1J30.27 deflect a rope
1J30.27 deflect a rope Stretch a rope in a frame with a 100 newton scale measuring the tension. Pull down with a 20 newton scale.
1J30.30 break wire with hinge
1J30.30 break wire with hinge Suspend a 5 kg mass from a length of wire. Break a length of similar wire by placing the same mass on the back of a large hinge.
1J30.30 breaking wire hinge Pushing down on a slightly bent hinge will break the wire fastened to the ends.
1J30.30 breaking wire hinge Press down on a hinge to break a rope.
1J30.35 pull the pendulum A long heavy pendulum is displaced with a spring scale.
1J30.40 horizontal boom
1J30.40 booms A sprig scale measures the tension in the supporting rope at various loads and boom angles.
1J30.40 horizontal boom The tension in the wire is measured with a spring scale for two different boom structures.
1J30.50 blackboard force table
1J30.50 blackboard force table Scales and masses are hung in front of a large movable whiteboard.
1J30.50 blackboard force table A weight is hung on a string suspended between two spring scales.
1J30.50 blackboard force table The standard blackboard force table.
1J30.50 blackboard force table A mass is hung from the center of a cord attached to two spring scales. Start with the strings vertical, increase the angle.
1J30.50 blackboard force table A force table in the vertical plane
1J30.50 force board This looks like a magnetic vertical force board. A circle is marked with angles every 10 degrees.
1J30.51 vertical force table A vertical force table that permits a continuous range of angles.
1J30.51 blackboard force table A removable frame that sets on the chalk tray.
1J30.51 blackboard force table A framework for doing the force table in the vertical plane.
1J30.52 force table on overhead A plexiglass force table for the overhead projector.
1J30.52 force table on OH proj Make a large sketch of the angles using the OH projector.
1J30.53 standard force table, etc. The standard force table, three dimensional force table, and torque apparatus.
1J30.54 force table Three scales and a ring to show forces add by parallel construction. Not the usual.
1J30.55 human force table
1J30.55 human force table Sit on a chair that hangs from a chain attached to load cells on each end.
1J30.55 human force table Hang from a large gallows frame on ropes attached to load cells.
1J30.55 bosun chair force table Sit on a chair suspended from two supports equipped with protractors and commercial load cells.
1J30.57 blackboard force table - rubber band Calibrate rubber bands for force vs. length, predict the mass of an object hung in a noncolinear configuration.
1J30.57 blackboard force table - rubber band A simple substitute for scales is a calibrated set of rubber bands.
1J30.57 blackboard force table - springs Use screen door springs in place of spring balances.
1J30.60 sail against the wind
1J30.60 sail against the wind Set a mainsail on a cart so it moves toward and away from a fan.
1J30.60 sail against the wind Use a large fan to blow at an air track glide with a sail.
1J30.60 sail against the wind A sail is mounted on an air track cart. A table fan supplies the wind.
1J30.60 sail and the wind Apparatus Drawings Project No.4: A sailboat rides in an air trough which serves as a keel. Set the angle of the sail with respect to the wind.
1J30.60 sailing upwind (airtrack) Use a skateboard cart with a foam core sail.
1J30.61 sail a trike against the wind A wind driven tricycle moves against the wind.
1J30.64 sail against the wind A wind driven boat accelerates against the wind. Description and Analysis.
1J30.64 sailboat and wind A cork stopper boat with a keel and removable sail.
1J30.65 floating cork A stick is hung by a thread at one end with the other attached to a cork floating on water.
1J30.65 floating cork A stick is hung by a thread at one end with the other attached to a cork floating on water.
1J30.70 sand in a tube
1J30.70 sand in a tube Place a tissue on the bottom of an open glass tube, fill with a few inches of sand, and push down on the top of the sand with a rod.
1J30.70 sand in a tube A couple of inches of sand held in a tube by tissue paper will support about 50 lbs.
1J30.75 stand on an egg
1J30.75 stand on an egg Three eggs in a triangle pattern in foam depressions between two plates will support a person.
1J30.75 egg crusher A raw egg can be squeezed between two hard foam rubber pads with a force of over 150 lbs.
1J30.80 rolling wedge A light roller lifts a heavy weight as it rolls inside an inclined hinge.
1J30.90 inverse catenary A string of helium balloons tied at each end forms an inverse catenary.
1J30.91 catenary analog computer Model the catenary on a simple analog computer.

40. Static Torque

1J40.10 grip bar A thin rod mounted perpendicular to a broom handle holds a 1 Kg mass on a sliding collar.
1J40.10 grip bar Use wrist strength to lift a 1 kg mass at the end of a rod attached to a broom handle.
1J40.10 grip bar Use wrist strength to try to lift 1 kg at the end of a rod attached perpendicularly to a handle.
1J40.10 grip bar A thin rod mounted perpendicular to a broom handle holds a 1 Kg mass on a sliding collar.
1J40.10 torque bar Use wrist strength to lift a weight suspended at various distances from the handle.
1J40.15 torque wrench
1J40.15 torque wrench Modify a Sears torque wrench so weights can be hung at different distances.
1J40.15 torque wrench A torque wrench is used to break aluminum and steel bolts.
1J40.16 different length wrenches
1J40.16 different length wrenches
1J40.20 meter stick balance Hang weights from a beam that pivots in the center on a knife edge.
1J40.20 torque beam Hang weights from a beam that pivots in the center on a knife edge.
1J40.20 torque beam Weights are hung from a horizontal bar pivoted on a knife edge.
1J40.20 torque beam Weights are hung from a meter stick suspended on a knife edge.
1J40.20 torque beam Weights on a meter stick supported at the center.
1J40.20 balancing meter stick Use a meter stick, suspended at the center, as a torque balance.
1J40.21 hinge board
1J40.21 hinge board Use a spring scale to lift a hinged board from various points along the board.
1J40.23 torque beam Put a quarter (5 g) on the end of a meter stick and extend it over the edge of the lecture bench until it is just about to tip over.
1J40.24 walking the plank
1J40.24 walking the plank Place a 50 lb block on one end of a long 2x6 and hang the other end off the lecture bench. Walk out as far as you can.
1J40.25 torque wheel
1J40.25 torque disc Weights can be hung from many points on a vertical disc pivoted at the center.
1J40.25 torque disc Various weights are hung from a board that can rotate freely in the vertical plane.
1J40.25 torque wheel Use a wheel with coaxial pulleys of 5, 10, 15, and 20 cm to show static equilibrium of combinations of weights at various radii.
1J40.26 torque disc An apparatus to show the proportionality between torsional deflection and applied torque.
1J40.26 torque disc Twist a shaft by applying coplanar forces to a disc.
1J40.27 torque double wheel
1J40.30 opening a door
1J40.30 opening door
1J40.32 opening a trapdoor
1J40.32 opening trapdoor
1J40.40 loaded beam
1J40.40 loaded beam Move a weight along a 2X4 on two platform scales.
1J40.40 loaded beam Large masses can be placed on a board resting on two platform balances.
1J40.40 loaded beam A model bridge is placed on two platform scales and a loaded toy truck driven across.
1J40.40 loaded beam A heavy truck is moved across a board supported on two platform scales.
1J40.40 bridge and truck A plank rests on two spring scales forming a bridge. Move a toy truck across.
1J40.41 loaded beam Support the loaded beam with spring scales instead of platform balances.
1J40.45 Galileo lever
1J40.45 Galileo lever Same as Sutton device.
1J40.45 Galileo lever A simple device to demonstrate the law of moments.
1J40.45 Galileo lever A simple device to show the law of moments.
1J40.50 Roberval balance
1J40.50 Roberval balance Large Roberval balance.
1J40.50 Roberval balance A reminder and picture of the Roberval balance. Reaction to TPT 21, 494 (1983).
1J40.50 Roberval balance A large model of the Roberval or platform balance.
1J40.50 Roberval balance Neutral equilibrium is maintained at any position on the platform.
1J40.51 Roberval balance A version of the Roberval balance where a rigid assembly has upper and lower arms on one side.
1J40.55 balances The equal-arm analytical balance and weigh bridge.
1J40.56 balances The steelyard.
1J40.60 suspended ladder
1J40.60 suspended ladder
1J40.60 suspended ladder Model of a ladder suspended from two pairs of cords inside an aluminum frame.
1J40.65 hanging gate
1J40.65 hanging gate A gate initially hangs on hinges, then add cords and remove the hinges leaving the gate suspended in mid air.
1J40.65 hanging gate Construction and use of a model of the swinging gate.
1J40.70 crane boom
1J40.70 crane boom
1J40.75 arm model
1J40.75 arm model Place a spring scale on a skeleton in the place of the biceps muscle and hang a weight from the hand.
1J40.75 arm model Use an arm model simulating both biceps and triceps muscles to throw a ball.

1K APPLICATIONS OF NEWTON'S LAWS

10. Dynamic Torque

1K10.10 tipping block Pull with a spring scale at various angles on the edge of a block.
1K10.10 tipping block A large wooden block is tipped over with a spring scale.
1K10.10 tipping block A spring scale is used to show the least force required to overturn a cube.
1K10.11 tipping blocks
1K10.11 tipping blocks Same as TPT 22(8),538.
1K10.11 tipping block Show the force necessary to tip over trapezoidal and weighted rectangular blocks. The students are surprised to discover the force needed is not related to the position of the center of mass.
1K10.20 ladder against a wall Set a model ladder against a box and move a weight up a rung at a time.
1K10.20 ladder against a wall A model ladder is set against a box and a weight moved up a rung at a time.
1K10.20 forces on a ladder A small model ladder is placed against a box.
1K10.20 ladder forces A real ladder leans against the wall. Animation shows the forces as the ladder moves.
1K10.25 forces on a ladder - full scale
1K10.25 forces on a ladder - full scale Mount a set of wheels at the top of a ladder, place some shoes at the bottom to decrease friction and climb the ladder until you fall down.
1K10.25 forces on a ladder - full scale Wheels are attached to the top of a ladder and the bottom slides on the floor. Climb up the ladder and fall down.
1K10.30 walking the spool Pull at various angles on the cord wrapped around the hub of a spool to move the spool forward or back.
1K10.30 walking the spool Pull on the cord wrapped around the hub of a spool at various angles to make the spool move forward or back.
1K10.30 walking the spool Pull on a cord wrapped around the axle of a large spool. The spool can be made to go forward or backward depending on the angle.
1K10.30 walking the spool A string is pulled off the inner axis of a spool at different angles, changing the direction the spool rolls.
1K10.30 walking the spool A string wound around the center of a spool is pulled at different angles causing the spool to change directions. Diagram and analysis. See TPT 2(3),139.
1K10.30 spool with wrapped ribbon The sides of the spool are made of clear plexiglass
1K10.31 walking the spool x three Three rolling spools where the outer discs ride on rails and the center section with the string is larger, smaller, and the same size as the outer discs allowing one to always pull horizontally.
1K10.40 pull the bike pedal
1K10.40 pull the bike pedal Lock the front wheel, remove the brake, add training wheels, and pull backwards on the pedal in the down position.
1K10.40 pull the bike pedal Pulling backward on a pedal (in the down position) of a brakeless bike will cause the bike to go back unless the length of the pedal crank is increased.
1K10.40 pull the bike pedal Pull backward on a pedal at its lowest point and the bike will move backward.
1K10.41 traction force roller
1K10.41 traction force roller Pull on a string wrapped around the circumference of a cylinder on a roller cart. Pull on a yoke attached to the axle of the same cylinder on the roller cart.
1K10.41 traction force roller A large pulley on a roller cart is drawn either by a string wrapped around the circumference or by a yoke attached to the axle.
1K10.41 traction force roller A large pulley can be drawn by either pulling on the axle or on a string wrapped around the perimeter. Try each case while the pulley is resting on a roller cart.
1K10.42 extended traction force
1K10.42 extended traction force Pull on a string wrapped around the circumference of a cylinder placed on an air track glider.
1K10.42 extended traction force A string wound around a cylinder, hoop, and spool is pulled while the objects are on a roller cart and the reaction force direction is surprising.
1K10.50 rolling uphill
1K10.50 rolling uphill A disc with a nonuniform mass distribution is placed on an incline so it rolls uphill.
1K10.50 rolling uphill A loaded disc is put on an inclined plane so it rolls uphill or rolls to the edge of the lecture bench and back.
1K10.50 rolling uphill A large wood disc weighted on one side will roll uphill or to the edge of a table and back.
1K10.50 loaded disc A loaded disc can roll up an incline.
1K10.80 teaching couples Start with two index fingers rotating a meter stick about the center of mass, use it to go into couples. Read it.
1K10.81 free vector A strong magnet on a counterbalanced cork always rotates about the center of mass no matter where the magnet is placed.
1K10.82 couples An arrangement to apply equal forces to opposite sides of a pulley mounted on a dry ice supported steel bar.
1K10.83 air jet couple Air from a balloon is released through two nozzles offset from the center of mass. The assembly is free to rotate on a block of dry ice.
1K10.90 saw-horse on teter-totter Good luck trying to demonstrate this one.

20. Friction

1K20.05 washboard friction model
1K20.05 washboard friction model
1K20.10 friction blocks - surface material Pull a block with four different surfaces with a spring scale.
1K20.10 friction blocks - surface material A set of blocks with different surfaces are pulled with a spring scale.
1K20.10 friction blocks Pull blocks across the lecture bench with a spring scale.
1K20.10 surface dependence of friction Place brass blocks on an incline with four surfaces: teflon, wood, sandpaper, and rubber.
1K20.12 friction blocks Several ways to move a surface under a fixed block.
1K20.13 sliding friction machine A spring scale is attached to an object on a rotating table.
1K20.13 friction blocks A device includes both sliding surface and mounted spring scale.
1K20.13 friction blocks A block is constructed with an built-in apparatus to measure coefficient of friction directly.
1K20.13 friction blocks An apparatus pulls a block at a constant speed and measures the frictional force. Details in appendix, p.550.
1K20.13 friction blocks A block rests on a turntable and the string goes to a dynamometer.
1K20.15 weight dependence of friction
1K20.15 weight dependence of friction Pull a friction block with a spring scale, add a second equal block to the first and repeat.
1K20.15 weight dependence of friction Add mass to a board pulled along the table with a spring scale.
1K20.16 friction blocks A loaded cart rolls down an incline and hits a barrier. The load continues sliding on a second incline until it stops. The mass on the slider is varied to show stopping distance independent of mass.
1K20.17 friction blocks Two additional points relating to Geoffery Fox's "Stumpers" column TPT. 11, 288 (1973).
1K20.20 area dependence of friction
1K20.20 area dependence of friction A friction block has a rectangular shape with one side twice as big as the other. One of the smaller sides is routed out to 1/5 the area.
1K20.20 friction blocks Friction independent of area of contact - cut a block to form a prism whose cross section is an irregular polygon.
1K20.20 area dependence of friction A 2X12 is pulled along the bench top while resting on either the narrow or wide face.
1K20.30 static vs. sliding friction Use a spring scale and block to show that static friction is greater than sliding friction .
1K20.30 static vs. sliding friction Show that static friction is greater than sliding friction with a spring scale and block.
1K20.35 angle of repose
1K20.35 angle of repose An incline plane is lifted until a block begins to slide.
1K20.35 angle of repose Using the familiar suspended incline block apparatus to examine normal and frictional forces in sliding up and down the plane.
1K20.35 angle of repose An inclined plane is raised until a block starts to slide.
1K20.37 tire friction The automobile tire is a misleading example of static and sliding friction.
1K20.37 tire skid equation Motivated by being an expert witness, An approximate expression for sliding friction coefficient as a function of speed was developed from published tables.
1K20.37 angle of repose A plastic small parts drawer on a sanded aluminum surface allows weight to be added easily.
1K20.37 angle of repose Using the incline plane for various friction demos.
1K20.38 how dry friction really behaves A note arguing that the main rules of thumb about friction are wrong and the less said about friction the better.
1K20.38 angle of repose A tribometer with a meter stick mounted vertically 1 m from the hinge gives a reading of coefficient of friction directly.
1K20.39 angle of repose Glass - glass angle of repose with oil and oil/water.
1K20.39 angle of repose The standard inclined plane and blocks + an interesting towel on a glass tube demo.
1K20.40 front and rear brakes
1K20.40 front and rear brakes A model car is rolled down an incline with either front or rear brakes locked.
1K20.40 front and rear brakes Construction details for a model car in which pulling a pin applies front, rear, or both sets of brakes to a car rolling down an incline.
1K20.40 front and rear brakes A car slides down an incline with either front or rear wheels locked.
1K20.40 front and rear brakes A car rolls down an incline with either front or rear wheels locked.
1K20.40 front and rear brakes A toy car is modified so either the front or rear brakes can be locked. Slide down the incline plane for each case.
1K20.40 stability of rolling car A toy car slides down an incline with either front or rear wheels locked.
1K20.42 friction roller
1K20.42 friction roller A cylinder in a yoke can be rolled or locked and slid as it is pulled by a spring scale.
1K20.42 friction roller A cylindrical roller is pulled or slid across the lecture bench with a spring scale.
1K20.42 friction roller A cylinder is pulled along and perpendicular to its axis by a yoke with a spring scale.
1K20.45 frictional force rotator
1K20.45 frictional force rotator
1K20.45 frictional force rotator This article shows how to rotate a friction vector to make its component in a given direction as small as desired. Everyday unconscious applications of this method are presented along with some new demonstration equipment.
1K20.46 cross friction Push a block across the slope of an incline and the block will move with a straight line trajectory. Knock a coin across and it will move in a curved path but all stopping points will be in a straight line.
1K20.55 squeaky chalk You don't have to break chalk to eliminate squeaking, only understand friction and hold the chalk accordingly.
1K20.55 angle of friction with pencil Tilt a pencil until it slides along the table.
1K20.60 sliding chain Hang a chain over the edge of the table until the weight of the chain makes it slide.
1K20.70 falling flask capstan
1K20.70 falling flask capstan Attach a 4 liter r.b. flask at the other end of a ball on a string and drape the flask over a horizontal rod 4' high. Let go of the ball.
1K20.70 falling keys capstan A short analysis of the falling key capstan.
1K20.70 falling keys capstan Hang a set of keys from a string draped over a pencil and when the string is released, the keys don't hit the floor.
1K20.71 discussion of the capstan Friction experiments with the cord wrapped around a cylinder. Discussion of the donkey engine and capstan with a digression on sea chanties.
1K20.71 capstan on a force table Tap a hole in the center of a force table and insert a bolt to use as a capstan.
1K20.71 capstan Theory of the capstan along with discussion of applications.
1K20.71 capstan Show the frictional force vs. the number of turns around a rod.
1K20.74 friction pendulum A ball is suspended by a loop of string over a slowly turning horizontal wooden bar. A large amplitude results.
1K20.76 going up a tree Very clever device. Look it up as its hard to describe.
1K20.80 Snoek effect If you don't know about the Snoek effect, don't ask me - I had to read up on it too.
1K20.85 WWII torpedo story Friction caused dud torpedo in WWII.
1K20.90 air track friction
1K20.90 air track friction Show there is little friction on an air track.
1K20.95 teflon cookie sheet Cut up a teflon coated cookie sheet for an inexpensive teflon surface.
1K20.95 teflon pulley Teflon sheet bent around corner replaces a pulley.
1K20.95 Dylite beads Dylite beads on a rimmed glass surface (window pane) provide a low friction surface.

30. Pressure 1K30.00 Pressure

1K30.10 bed of nails Lie down on a bed of 16d nails on 1" centers.
1K30.10 bed of nails Lie down on a bed of 16d nails on 1" centers.
1K30.10 bed of nails The instructor lies on a large board with nails at 1" centers.
1K30.10 bed of nails Break a block on the chest of a person lying on a bed of nails.
1K30.20 pop the balloons
1K30.20 pop the balloons A disc with points on one side can be placed on balloons so either the points or flats rest on the balloons.

1L GRAVITY

10. Univ. Gravitational Constant 1L10.00 Univ. Gravitational Constant

1L10.01 falling apple story Quotes from the original accounts of the falling apple and Newton.
1L10.10 Cavendish balance film loop Time lapse of the Cavendish experiment.
1L10.10 Cavendish balance film loop Time lapse of the Cavendish experiment.
1L10.20 Cavendish balance model
1L10.20 Cavendish balance model A model of the Cavendish balance with sliding masses.
1L10.20 Cavendish balance model Model of the Cavendish balance.
1L10.30 Cavendish balance
1L10.30 Cavendish balance Set up the standard Cavendish balance with a laser beam.
1L10.30 Cavendish balance A platform is used to decouple the Cavendish balance from the building vibrations.
1L10.30 Cavendish balance Quite a bit of discussion about the Klinger KM 1115 gravitational torsion balance.
1L10.30 Cavendish balance Standard Cavendish experiment with lead balls and optical lever detection.
1L10.30 Cavendish balance Mount the Cavendish balance permanently in the classroom and adjust hours before the experiment.
1L10.30 Cavendish balance The commercial device with video over a 1 1/2 hour period.
1L10.33 Cavendish balance - damping A small ball bearing attached to the bottom of the vane dips into a cup containing silicon oil.
1L10.34 Cavendish balance wire replacement Use amorphous metallic ribbon as a wire replacement which gives a higher spring constant and is more durable.
1L10.35 do-it-yourself Cavendish balance A simple Cavendish balance built by sophomore students.
1L10.36 modified torsion balance A very small suspension wire is used allowing the linear accelerations to be measured directly.
1L10.41 resonance Cavendish balance The Cavendish balance is driven into resonance by swinging the external mass. Suitable for corridor demonstration.
1L10.42 servo mechanism Cavendish balance Abstract from the apparatus competition.
1L10.42 servo mechanism Cavendish balance The torsion bar does not appreciably rotate. A simple electronic servomechanism is used to maintain rotational equilibrium as an external mass is introduced. The resulting servo correction voltage is proportional to the torque introduced by gravity. This effect can be observed in tens of seconds.
1L10.43 Cavendish balance compensation Modify the Leybold Cavendish balance with a electromagnetic servosystem of damping that reduces the settling time to a few minutes.
1L10.45 automatic recording Cavendish The reflected laser light from the Cavendish balance falls on a two-element photodiode mounted on a strip chart recorder with appropriate electronics to keep the spot centered on the diode.
1L10.50 gravitational field model
1L10.50 gravitational field model

20. Orbits

1L20.10 gravitational well - rubber diaphragm
1L20.10 gravitational well On making a rubber diaphragm type potential well.
1L20.12 gravitational well on OH proj Making a Lucite 1/R surface for use on the overhead projector.
1L20.14 elliptic motion A ball rolling in a funnel or cone.
1L20.16 gravity surface Using the Playskool Baby Drum Drop as a gravity surface.
1L20.17 orbits in a wineglass A properly shaped wine glass is used with ball bearings to show radius to orbit period, orbit decay, etc.
1L20.18 orbits in a spherical cavity Derivation of the period of a ball orbiting in a spherical cavity. Strobe photography verifies as a demo.
1L20.30 rotating gravitational well A ball placed in a rotating potential well demonstrates the path of a satellite. Use a variable speed motor to show escape velocity.
1L20.31 escape velocity A Fake. Pour water into a can with a hole in it and then twirl around until "escape velocity" is reached. Show no water remains.
1L20.32 satellites A very complex satellite simulator.
1L20.35 spin-orbit coupling A spinning ball orbits in a watch glass with increasing radii until it escapes.
1L20.36 film "Motion of Attracting Bodies"
1L20.36 "Motion of Attracting Bodies" film Meeks film, 6:30 min. Computer animated. Covers Newton's laws, earth's gravity variations, satellite and binary orbits.
1L20.40 conic sections
1L20.40 conic sections A dissectible cone is cut several ways to give a circle, ellipse, parabola, and hyperbola.
1L20.40 sections of a cone The standard wood cone.
1L20.45 drawing ellipses The two nail and string method for ellipse drawing.
1L20.50 ellipse drawer
1L20.50 ellipse drawer
1L20.50 ellipse drawer An aluminum bar with adjustable pegs and a loop of string for drawing the ellipse.
1L20.51 ellipse drawing board The two nail and string method of drawing on paper.
1L20.55 orbit drawing machine Design for orbit drawing machines for use on the overhead projector. A simple one draws elliptical orbits only, an elaborate one draws general Coulomb orbits.
1L20.61 dry ice puck orbits A dry ice puck on a large table is tethered through a hole in the center to a vacuum ping pong ball device under the table that gives an inverse square law force. Construction details p.573.
1L20.62 dry ice puck Kepler's law A dry ice puck has a magnet mounted vertically with a second one below the table which may be inverted to show both attraction and repulsion.
1L20.62 dry ice puck Kepler's law A strong magnet is placed under the air table and a magnetic puck with a light is photographed.
1L20.62 air table Kepler's laws With a strong magnet below the table, take strobe photos of a magnetic puck to demonstrate equal areas. TPT 8(4),244.
1L20.63 dry ice puck Kepler's law Motor at the center of the table with a special pulley arrangement.
1L20.64 areal velocity conservation Analyze a strobe photograph of one cylindrical magnet on dry ice approaching another and deflecting.
1L20.65 fancy air puck Kepler's law The puck has a variable thruster and is of variable mass. A Peaucellier linkage is used to apply central force.
1L20.66 "gravity" with magnetic field Drop a ball near a magnetron magnet and watch it curve around about 150 degrees.
1L20.69 inverse square law motion Pointer to A-62, A-63. Very crude models of planetary motion.
1L20.71 film "Planetary Motion and Kepler's Laws"
1L20.71 "Planetary Motion and Kepler's Laws" Meeks film, 8:45 min. Computer Animated. Shows orbits of the planets, covers Kepler's second and third laws.

1M WORK AND ENERGY

10. Work

1M10.10 shelf and block
1M10.10 shelf and block Lift a block up and set it on a shelf.
1M10.15 block on table
1M10.15 block on table
1M10.16 carry a block
1M10.16 carry a block Just carry a block around.
1M10.20 pile driver Drive a nail into a block of wood with a model pile driver.
1M10.20 pile driver A model pile driver pounds a nail into wood.
1M10.20 pile driver A 10 lb block guided by side rails falls onto a nail in wood.
1M10.20 pile driver Drive a nail into a block of wood with a model pile driver.
1M10.20 pile driver Drop a weight onto a nail in wood.
1M10.25 pile driver with pop cans
1M10.25 pile driver with soda cans Smash pop cans with a pile driver.
1M10.99 work to remove tape Pull off a piece of tape stuck to the lecture bench.

20. Simple Machines

1M20.01 simple machine collection
1M20.01 simple machines A collection of simple machines is shown.
1M20.10 pulleys
1M20.10 pulleys An assortment of large pulleys can be rigged several ways.
1M20.10 pulleys Demonstrate what you have.
1M20.11 pulley advantage
1M20.11 pulley advantage Place a mass on a string over a pulley and hold a spring scale at the other side. Repeat with a mass hanging from a single pulley in a loop of string.
1M20.11 pulley advantage Hang a 10 newton weight on a string passing over a pulley and measure the force with a spring scale, then hang the weight from a free running pulley.
1M20.13 pulleys Pedagogy. Good diagram.
1M20.15 pulley and scales
1M20.15 pulley and scales Same as encyclopedia disc 04-05.
1M20.15 pulley and scales This is a counter intuitive demonstration. A frame containing a spring scale and pulley hangs from another spring scale. Look it up.
1M20.20 bosun's chair
1M20.20 bosun's chair Use a single pulley to help the instructor go up.
1M20.20 bosun's chair Using a block and tackle, the lecturer ascends. Full of pedagogical hints on how to do this effectively.
1M20.20 bosun's chair The instructor "lifts himself up by the bootstraps".
1M20.25 monkey and bananas
1M20.25 monkey and bananas A wind up device and equal mass are placed at either ends of a string placed over a pulley.
1M20.25 monkey and bananas A yo-yo and counterweight are suspended over a pulley. The counterweight and yo-yo rise and fall together.
1M20.25 monkey and the coconut A steel yo-yo and steel counterwieght suspended over two low friction bearings.
1M20.25 climbing monkey A yo-yo and a counterweight are on opposite sides on a pulley. As the yo-yo goes up and down, so does the counterweight.
1M20.25 climbing monkey A steel yo-yo on one side of a pulley and a counterweight on the other. As the yo-yo goes up and down, so does the counterweight.
1M20.26 climbing monkey Two equal masses are hung over a pulley, one of which is equipped with a cord winding mechanism.
1M20.27 windlass A model windlass is described.
1M20.28 climbing pirate String is wrapped around two different sized pulleys on a common axis.
1M20.29 fool's tackle A diagram of the "fools tackle" is shown.
1M20.30 incline plane
1M20.30 incline plane
1M20.30 screw and wedge A long triangular piece of sailcloth is wound around a mailing tube to show the relationship between a screw and a wedge. Diagram.
1M20.35 big screw as incline plane
1M20.35 big screw A large wood screw and nut (6"-1) show the relationship between a screw and incline.
1M20.40 levers
1M20.40 levers Show the three classes of levers with a mass, bar, pivot, and spring scale.
1M20.40 levers The three classes of simple levers.
1M20.40 levers A torque bar, spring scale, and pivot are used to illustrate the three classes of levers.
1M20.45 body levers
1M20.45 body levers Construction and use of a device representing body levers.
1M20.60 wheel and axle The PIC-Kit used for demonstrating simple machines.
1M20.99 black box Hide a mechanism in a box and try to deduce what is inside.

30. Non-Conservative Forces

1M30.10 air track collision/sliding mass
1M30.10 air track collision/sliding mass An air cart with a mass that can be locked or free hits the end of the track.
1M30.10 air track collision/sliding mass Compare the bounce of an air cart on an inclined air track with a mass that is attached tightly and loosely.
1M30.15 neg.accelaration due to friction A pendulum hits a tabletop, transferring a wood block rider to the tabletop. Potential to kinetic energy is wasted in friction.
1M30.16 ref. friction blocks see 1K20.16.
1M30.30 the woodpecker A toy bird slides down a rod giving up energy to friction and pecking. A "loose clamp" on the ringstand demo is also shown.

40. Conservation of Energy

1M40.10 nose basher A bowling ball pendulum is held against the nose and allowed to swing out and back.
1M40.10 nose basher Hold a bowling ball suspended from the ceiling against your nose and let it swing.
1M40.10 nose basher, etc Use bowling balls for the nose basher, drop out or project out of upper floor windows, collisions.
1M40.10 nose basher A large pendulum bob is suspended from the ceiling. Do the nose basher.
1M40.10 nose basher Head against the blackboard, long pendulum.
1M40.10 nose basher Hold a bowling pendulum to the nose and let it go.
1M40.10 nose basher / bb pendulum A bowling ball pendulum is held against the nose and allowed to swing out and back.
1M40.11 recording pendulum motion A complicated device uses a spark timer to record interchange of kinetic and potential energy in a swinging pendulum.
1M40.12 additional references A letter noting that AJP 35(11),1094 has been published many times.
1M40.12 weight of a pendulum Suspend a pendulum from a double beam balance with a small block placed under the opposite pan to keep the system level. Swing the pendulum so it just lifts a weight off the stopped pan.
1M40.12 swinging on the halyards Swinging on the halyards to hoist a sail.
1M40.12 break a pendulum wire Suspend a heavy bob on a weak wire. As the ball descends in its swing, the wire breaks.
1M40.13 burn the pendulum wire A Saran wrap pendulum support is burned to release the bob as it reaches the bottom of its swing. Measure the range of the bob.
1M40.15 stopped pendulum A pendulum started at the height of a reference line reaches the same height when a stop is inserted.
1M40.15 stopped pendulum A pendulum is started at the height of a reference line and returns to that height even when a stop is inserted.
1M40.15 stopped pendulum A pendulum swing is started at the height of a reference line. A stop is inserted and the bob still returns to the same height.
1M40.15 Galileo's pendulum Intercept the string of a pendulum by a post at the bottom of the swing.
1M40.16 blackboard stopped pendulum Do the stopped pendulum on the blackboard.
1M40.20 loop the loop A ball rools down an incline and then around a vertical circle.
1M40.20 loop the loop A ball rolls down an incline and around a loop. Vary the initial height of the ball.
1M40.20 loop the loop Apparatus Drawings Project No. 26: The vertical circle is made by flexing a thin stainless steel strip in a framework of plexiglass.
1M40.20 loop the loop How to make an inexpensive loop the loop from vinyl cove molding.
1M40.20 loop the loop A steel ball is rolled down an angle iron bent to form a incline and loop.
1M40.20 loop the loop An apparatus to do the loop the loop quantitatively. Construction details in appendix, p.589.
1M40.20 loop the loop A ball rolls down an incline and then around a vertical circle.
1M40.20 loop the loop Standard loop the loop.
1M40.20 loop the loop A rolling ball must be released at 2.7 times the radius of the loop.
1M40.21 water loop the loop A water stream "loop the loop" demonstrates the effect of centripetal forces much more dramatically then when a ball is used.
1M40.23 reverse loop the loop
1M40.23 reverse loop the loop The reverse loop-the-loop is placed on a cart hooked to a falling mass that produces an acceleration just large enough to make the ball go around backwards into the cup.
1M40.23 reverse loop-the-loop With a little practice, one can pull a reverse loop-the-loop with a large and prolonged acceleration. Plans and procedures.
1M40.23 reverse loop the loop In the reverse loop-the-loop a ball rolls up an incline and around a loop into a cup as the whole apparatus is accelerated.
1M40.24 loop the loop with slipping analysis Analysis of loop the loop, also dealing with slipping.
1M40.25 energy well track
1M40.25 energy well track A ball can escape the energy well when released from a point above the peak of the opposite side.
1M40.30 ball in a trough
1M40.30 ball in a track A ball rolls in an angle iron bent into a "v" shape.
1M40.30 ball in a trough Roller coaster car on a track runs down one track and up another of a different slope.
1M40.31 deformed air track Deform a 5 m air track into a parabola (1") at center and show oscillations both with the track leveled and with one end raised.
1M40.31 air track potential well Curve an air track into an arc of a vertical circle.
1M40.32 ball in curved tracks Balls are rolled down a series of curved tracks of the same height but different radii.
1M40.33 triple track
1M40.33 adjustable track
1M40.33 ball in a track A large steel ball rolls on a bent angle track with differing slopes.
1M40.33 triple track energy conservation Balls released from three tracks with identical initial angles rise to the same height independent of the angle of the second side of the "v".
1M40.35 roller coaster
1M40.35 roller coaster A ball rolls down a track with four horizontal sections of differing heights. The velocity is measured at each section.
1M40.35 roller coaster experiment Optoelectrical detectors measure the speed of a ball at specific points on a roller coaster track. Could be adapted for lecture demonstration.
1M40.40 ballistic pendulum with .22
1M40.40 ballistic pendulum Shoot a .22 into a block of wood mounted as a pendulum. A slider device measures recoil.
1M40.40 ballistic pendulum A .22 is fired into a suspended wood block. The recoil distance is used to determine the rise of the block.
1M40.40 ballistic pendulum Shoot a .22 straight up into a suspended block of wood.
1M40.40 ballistic pendulum The standard rifle ballistic pendulum setup.
1M40.40 ballistic pendulum Fire a air-gun into a wood block with a paraffin center.
1M40.41 Beck ballistic pendulum
1M40.41 modify the ballistic pendulum Ignoring rotational dynamics results in a large error. Convert to a rotational dynamics device with an additional metal sleeve.
1M40.41 Beck ballistic pendulum Comprehensive review of the Beck ballistic pendulum.
1M40.41 ballistic pendulum The commercial ballistic pendulum.
1M40.41 ballistic pendulum The commercial swinging arm ballistic pendulum.
1M40.42 ballistic pendulum A catapult/ballistic pendulum made of inexpensive materials.
1M40.43 bow and arrow ballistic pendulum The relation between bending of the bow and the velocity of the arrow was found to be linear.
1M40.43 bow and arrow ballistic pendulum Plans for a coffee can target for a bow and arrow ballistic pendulum. Includes slider.
1M40.45 blow gun ballistic pendulum Find the velocity of the dart fired from a blowgun by measuring the fall from the aiming point to the hit point on the target block.
1M40.47 vertical ballistic pendulum A ball is dropped into a box of sand suspended from a spring and the extension of the spring is measured.
1M40.49 trouble with the ballistic pendulum An analysis of the error introduced with non-parallel ropes.
1M40.49 ballistic pendulum tutorial Good tutorial on the ballistic pendulum.
1M40.50 big yo-yo
1M40.50 big yo-yo A large disc is hung from bifilar threads wrapped around a small axle.
1M40.50 big yo-yo A shop drawing of axles with three different radii used to make a big yo-yo out of a force table.
1M40.50 big yo-yo A large (2') disc is suspended from a small axle so the string unwinds on the way down and rewinds on the way up.
1M40.50 big yo-yo Two large discs hung from bifilar thread wrapped around a small axle.
1M40.50 big yo-yo A large yo-yo is made by suspending a large spool from two threads wrapped around opposite ends of the axle.
1M40.50 big yo-yo A picture of a commercial Maxwell's wheel.
1M40.50 Maxwell's yoyo Release a large yo-yo and it will bottom out and wind up again.
1M40.51 cheap and simple yo-yos Yo-yos made with cardboard sides and paper towel centers routinely gave time of fall within 1% of predicted
1M40.55 swinging arm A ball is dropped into a pivoting capturing arm from the height required to make it just complete one revolution.
1M40.56 spinner and pendulum A ball suspended as a bifilar pendulum hits a ball of equal mass free to rotate in a horizontal circle.
1M40.57 Pany device A complicated apparatus converts elastic potential energy (spring) into rotational potential energy and back.
1M40.60 height of a ball
1M40.60 height of a ball Same as AJP 29(10),709.
1M40.60 height of a ball Rotate a 15.3 in radius bar at 1, 2, or 3 rev/sec, a mechanism releases a ball at the end of the bar at the moment the ball is traveling vertically. The ball rises 1, 4, or 9 ft.
1M40.60 height of a ball A device to project a ball upward at different known velocities to show dependence of kinetic energy on the square of velocity.
1M40.61 1-D trampoline
1M40.61 1-D trampoline A horizontal string passes over a pulley down to a spring fixed at one end. Place a spitball at the center of the horizontal section and pull it down until the spring extends unit lengths. Compare the heights the spitball reaches.
1M40.63 x-squared spring energy dependence
1M40.63 x-squared spring energy dependence Measure the height of recoil on an air cart glider on an incline after compressing a spring different to different lengths.
1M40.64 spring ping pong gun
1M40.64 spring pong gun A spring gun shoots standard and loaded ping pong ball to different heights.
1M40.65 height of a spring launched ball
1M40.65 height of a spring-launched ball A 3/4" steel ball is launched upward by a "stopped spring" (shown), from which the initial velocity is calculated.
1M40.66 mechanical jumping bean
1M40.66 mechanical jumping bean Same as TPT 1(3),108.
1M40.66 mechanical jumping bean A mailing tube jumps when a hidden mass moves upward under rubber band power.
1M40.66 jumping tube A spring loaded tube jumps two or three times its own height when triggered. Diagram.
1M40.67 spring jumper
1M40.67 spring jumper Compress a spring under a toy held down be a suction cup.
1M40.68 muzzle velocity - spring constant A method of using the potential energy of the cocked spring to calculate the muzzle velocity. (15% of the energy is lost.)
1M40.69 rachet for inelastic collisions A ratchet mechanism locks a spring in the compressed position giving an inelastic collision with the decrease in kinetic energy stored for later release by tripping the ratchet.
1M40.71 dropping bar Lift a horizontal bar suspended from two springs and drop it through a photocell to measure velocity. Examine the exchange between gravitational, elastic potential, and kinetic energy.
1M40.72 tension in wire when one mass swings A spring scale is suspended between two masses. Set one swinging- a lot of physics.
1M40.74 air track cart and falling mass A mass m attached to a cart M with a string and pulley. Compare kinetic energy gained by m+M with potential energy lost by M.
1M40.75 obedient can
1M40.76 air disc A falling weight spins an air bearing supported rotating disc. Compare rotational (disc) and translational (weight) kinetic energy with potential energy.
1M40.80 push-me-pull-you sternwheeler Both upstream and downstream motion is possible in a system with a water stream running between the rails and a waterwheel mounted on the rear axle of the cart.
1M40.85 sloping cart This is a counter intuitive demo. Nothing happens when a brick is placed on a slanted cart.
1M40.90 rattleback
1M40.90 rattleback
1M40.91 high bounce paradox
1M40.91 high bounce paradox Flip a half handball inside out and drop on the floor. It bounces back higher than the height from which it was dropped.
1M40.93 acrobat ?????????????

50. Mechanical Power

1M50.10 Prony brake Turn a large hand cranked pulley with the belt fastened to two spring scales.
1M50.10 Prony brake A belt fastened to two spring scales is strung under tension around a large hand cranked pulley.
1M50.10 Prony brake How to make a self adjusting Prony brake that provides constant torque.
1M50.10 Prony brake Each end of the belt for a Prony brake is attached to a spring scale.
1M50.10 Prony brake Measuring your horsepower by Prony brake and running up stairs. Hints on making a human sized Prony brake.
1M50.10 Prony brake Measuring delivered horsepower by turning a pulley under a stationary belt attached to spring scales at each end.
1M50.10 Prony brake Rotate a shaft against a constant frictional resistive force.
1M50.20 power bicycle Attach a 2" dia. axle to the rear of a bike and use it to lift a weight via a pulley on the ceiling.
1M50.30 ref. hand crank generator see 5K40.80.
1M50.50 rocket wheel Two rockets are mounted on the rim of a bike wheel. The second is fired after effect of the first has been measured showing the power developed by a rocket is a function of its velocity

1N LINEAR MOMENTUM AND COLLISIONS

10. Impulse and Thrust

1N10.10 collision time pendula
1N10.10 collision time pendula An electronic timer measures the impact time as two pendula collide.
1N10.10 collision time pendula Two metal wire bifilar pendula are suspended as part of a circuit to measure contact time on a counter.
1N10.11 time of contact A steel ball suspended from a conducting wire hits a vertical steel plate and the electrical signal gives time of contact.
1N10.12 fleeting event timer Hitting two hammers together gates a fast oscillator to a counter.
1N10.12 contact time by oscillator A ball swings against a plate completing a circuit allowing an oscillator to feed a counter to measure collision time.
1N10.13 measuring impulse A pendulum strikes a piezoelectric crystal and generates a voltage spike which is viewed on an oscilloscope.
1N10.14 measuring impulse by induction A pendulum strikes a magnet moving it in a coil inducing a current that deflects a galvanometer.
1N10.15 silicone ball on blackboard
1N10.15 silicone ball on blackboard Throw a silicone ball at a dirty blackboard, measure the diameter of the mark, and place weights on the silicone ball until it is squashed to the same diameter.
1N10.15 ball on the blackboard Compare the imprint of a sponge ball thrown against a dirty blackboard with the force required to get an equal size deformation and calculate the interaction time.
1N10.16 deform clay Drop a 50 g mass on some softened clay, then add masses slowly to another blob of clay until the depression is equal.
1N10.20 egg in sheet Throw an egg into a sheet held by two students.
1N10.20 egg in sheet Throw an egg into a sheet held by two students.
1N10.20 egg in sheet Throw an egg at a sheet held by two people.
1N10.25 drop egg in water
1N10.25 drop egg in water
1N10.30 pile driver with foam rubber
1N10.30 pile driver with foam rubber Break a bar of plexiglass supported on two blocks with a pile driver. Add foam to a second bar and it doesn't break.
1N10.30 piledriver with foam rubber A pile driver breaks a plastic sheet supported at the sides. Add a piece of foam rubber and the plastic does not break.
1N10.35 car crashes
1N10.35 car crashes Roll a car down an incline to smash beer cans. Vary the bumpers to change the impulse.
1N10.35 car crashes A cart rolls down an incline and smashes a beer can against a brick wall. Four interchangeable bumpers are used to vary the impulse.
1N10.36 car saftey on the air track Models of a person with a head, seat belt and a head rest are placed on an air track cart.
1N10.40 auto collision videodisc
1N10.40 auto collision videodisc Show segments of the video disc.
1N10.50 impulse on the air track A rubber band launcher provides an impulse to an air cart. Analysis given is for a lab.
1N10.50 impulse acceleration track A mass on a right angle lever imparts a known variable impulse to a cart on a track and the final velocity is measured.
1N10.55 karate blows Not many physics instructors will be able to perform these demonstrations.
1N10.55 karate strikes Analysis of karate strikes and description of breaking demonstrations.
1N10.56 water stream impulse The force created by a momentum change in a fine water stream is calculated using measurements obtained with a large scale impulse balance. Construction details.
1N10.57 jet velocity by impulse The impulse supplied by the counterweight equals the loss of horizontal momentum of a jet of water. The exit velocity of the water jet is then calculated and checked by measuring range.
1N10.63 thrust with air carts Two carts, one with an air nozzle, the other with a reversible hemispherical deflector can be connected by a spring to show forces internal and external to a system and the effects on thrust resistance and thrust reversal.
1N10.64 water jet thrust Measure the vertical height of a water jet, collect water to determine the flow, and match the deflection of the nozzle by hanging weights with the flow turned off.
1N10.70 model rocket impulse
1N10.70 model rocket impulse Using solid fuel model rocket engines as an impulse generator, demonstrate the impulse-momentum theorem by measuring the final velocity.
1N10.71 model rocket thrust A device provides a method of measuring the thrust of a model rocket engine and recording it on graph paper. Impulse is calculated. Clever.
1N10.72 model rocket thrust Modify a toy rockets to maintain continuous discharge. Attach to a platform scale.
1N10.74 model rocket thrust An apparatus designed to measure the thrust of a rocket is used to check the manufacturer's specifications.
1N10.75 Dyna-Jet thrust Thrust measurements are made on a pulse jet engine (Dyna-Jet).
1N10.80 fire extinguisher thrust
1N10.80 fire extinguisher thrust Measure the thrust of a fire extinguisher.
1N10.81 measuring impulse Complete treatment of the fire extinguisher cart to get exhaust velocity and average thrust for a variable mass system.
1N10.85 air cart rocket thrust A device (diagram) measures thrust of a gas propelled air cart. Speed and acceleration are determined by strobe photography.
1N10.90 thrust independent of medium A rocket pendulum maintains the same angle of recoil in air or water showing thrust is independent of medium.

20. Conservation of Linear Momentum

1N20.10 see-saw center of mass
1N20.10 see-saw center of mass Two carts magnetically repel each other on a teeter-totter. Mass of cars can be varied.
1N20.10 see-saw center of mass Magnet carts on a balanced board repel when a constraining string is burned. Also load carts unequally.
1N20.10 magnetic reaction carts Two carts with opposing permanent magnets are held together by a string which is burned.
1N20.10 see-saw center of mass Magnet cars on a balanced board repel each other when a constraining string is burned. Carts may be loaded unequally.
1N20.10 see-saw canter of mass A string holding two carts with opposing horseshoe magnets is burned and they remain balanced on a board as they repel.
1N20.10 see-saw center of mass Two spring loaded carts repel each other on a balanced board.
1N20.10 see-saw reaction carts Two spring loaded carts repel each other on a balanced board.
1N20.12 rolling ball on air cart A ball rolls down a small inclined plane mounted on an air track. Watch the glider start and stop.
1N20.15 car on a rolling board
1N20.15 car on a rolling board Start and stop a radio controlled car on a board on rollers.
1N20.15 car on a rolling board A straight train track is mounted on a movable board. Changing the weighting of the train will change the relative velocities of the train and track. Use a circular track for conservation of angular momentum.
1N20.15 car on rolling board Use a radio-controlled car on the board on a series of rollers.
1N20.16 car on the road A drawing board rides on perpendicular sets of steel rods to give 2D freedom of motion. Set a toy wind up car on it.
1N20.17 train on an air track An HO gauge train and 36" track mounted on a air cart.
1N20.20 sprring apart air track gliders Burn a string holding a compressed spring between two air gliders.
1N20.20 spring apart air track glider Two spring loaded carts carts on the air track initially held together by a electromagnet repel and are timed photoelectrically.
1N20.20 spring apart air track glider Air track carts equipped with iron cores and a spring are held together by an electromagnet.
1N20.20 spring apart air track glider Compress spring and burn thread to release, or use a toy pistol cap and hand held tesla coil.
1N20.20 reaction gliders momentum conservati Burn a string holding a compressed spring between two unequal mass air gliders.
1N20.21 old reaction carts Two spring loaded carts on a track with light bulbs at the ends of the track to indicate simultaneous arrival.
1N20.21 old reaction cars Two spring loaded cars on a track fly apart. If they reach the ends at the same time, lights flash.
1N20.22 repelling carts Two carts on a track start at rest and are exploded and timed.
1N20.23 magnetic release The magnetic release for the spring apart air track carts.
1N20.24 recoiling magnets Hold two small horseshoe magnets together on an overhead projector and observe the recoil.
1N20.25 elastic band reaction carts
1N20.25 elastic band reaction carts Pull apart two carts of unequal mass attached with an elastic band.
1N20.25 elastic band reaction cars A stretched rubber band pulls two carts together with accelerations inversely proportional to their masses.
1N20.30 exploding pendula Two large pendula of unequal mass are held together compressing a spring. When the spring is released, two students mark the maxima.
1N20.31 reaction swings Planks with bifilar supports may be used in place of reaction carts.
1N20.32 exploding basketballs Explode a firecracker between a light and heavy basketball that are suspended near the ceiling. Details of the basketball holder are given.
1N20.32 big bertha A dry ice cannon is mounted on model railroad tracks. Average velocity of the recoiling cannon and projectile are timed.
1N20.35 explosion Explode a firecracker in an iron block 4x4x2" pieced together from three sections.
1N20.35 explosion - comment about friction The center of mass will move due to friction.
1N20.60 air track c of m collision An inelastic air track collision with a cart and a spring coupled cart system.

21. Mass and Momentum Transfer

1N21.10 floor carts and medicine ball
1N21.10 floor carts and medicine ball Two people on roller carts throw a medicine ball to each other.
1N21.10 floor carts and medicine ball Throw a medicine ball or baseball back and forth, throw several baseballs against the wall.
1N21.20 catapult from cart to cart
1N21.20 catapult from cart to cart Catapult a ball on equal mass as the cart into a catcher in the second cart.
1N21.20 catapult from cart to cart Two carts at rest on a track, one catapults a steel ball into the other, each is photoelectrically timed.
1N21.25 thrust cars Conservation of momentum of a thrust producing stream on water is shown by two carts on a track: one has a nozzle, the other a bucket to catch the water.
1N21.26 thrust cars How to pull the plug on a container of water on a cart to show conservation of momentum by reaction to discharging water stream.
1N21.30 ballistic air glider
1N21.30 ballistic air glider Shoot a .22 into a wood block mounted on an air glider. Use a timer to determine the velocity.
1N21.30 ballistic air glider Shoot a 22 into a block of wood on an air cart.
1N21.30 ballistic air glider A .22 is fired into a block of wood mounted on an air cart.
1N21.30 ballistic air glider A rifle is shot into a car on a track.
1N21.30 ballistic air glider Shoot a .22 into a block on an air cart.
1N21.40 drop sandbag on cart
1N21.40 drop sandbag on cart A cart passes by a device that drops a sandbag of equal mass as the cart. Timers measure the velocity before and after the transfer.
1N21.40 drop weight on moving cart Drop a weight on a moving cart, two people on roller carts push against each other.
1N21.41 drop shot on cart Lead shot is dropped from a hopper into a box on a moving cart. The initial velocity is reproducible and the final velocity is measured with a photogate.
1N21.45 vertical catapult from moving cart
1N21.45 vertical catapult from moving cart Shoot a ball of equal mass from a moving cart into a catcher. Time to determine the velocity before and after the transfer.
1N21.50 jump on the cart Run at constant velocity and jump on a roller cart.
1N21.55 air track ball catcher Shoot a stream of balls at a moving air cart until the cart stops.

22. Rockets

1N22.01 historical note An article claims rockets will not work in space because there is nothing to push against.
1N22.10 fire extinguisher wagon Mount a fire extinguisher on a cart and take a ride.
1N22.10 fire extinguisher rocket Mount a fire extinguisher on a cart and take a ride.
1N22.10 fire extinguisher wagon Mount a fire extinguisher on a wagon with the hose attached to a half inch plumbing fitting directed to the rear.
1N22.15 rocket lift-off video
1N22.15 rocket video Show video of a rocket or shuttle launch.
1N22.20 water rocket Pump a toy water rocket the same number of times, first with only air, and then with water.
1N22.20 water rocket Pump a toy water rocket the same number of times, first with only air, and then with water.
1N22.20 water rocket A commercial water rocket is charged with air and then water.
1N22.20 water rocket Use a water rocket first with air only, and then with air and water.
1N22.23 air track rocket Air from a rubber balloon propels an air cart.
1N22.25 balloon rocket
1N22.25 balloon rocket "Balloon rockets" are available at toy stores. Normal balloons follow more random paths.
1N22.30 CO2 cartridge rocket
1N22.30 rocket car A CO2 powered car accelerates across the lecture bench.
1N22.30 rocket car - CO2 cartridge Cartridges of CO2 are used to propel small automobiles or projectiles.
1N22.32 rocket to the Moon A nice setup of the CO2 rocket on a wire.
1N22.32 rocket to the Moon A small CO2 powered rocket rides a wire across the classroom.
1N22.33 rocket around the Moon
1N22.33 rocket around the Moon A CO2 cartridge in the back of a model plane propels it around in circles.
1N22.33 CO2 rocket A small CO2 cartridge rotates a counterbalanced bar.
1N22.40 ball bearing rocket cart
1N22.40 ball bearing rocket cart A cart is propelled down a track by 2 1/2" ball bearings rolling down a chute attached to the cart.
1N22.40 ball bearing rocket cart A cart is propelled down a track by 1" ball bearings rolling down a chute.
1N22.40 ball bearing rocket cart Fifteen large steel ball bearings fall through a chute to propel a cart. The last ball moves in the same direction as the cart.
1N22.51 reaction to a stream of water A nozzle reacts against a water jet.
1N22.51 reaction to a stream of water Several techniques on making the deflection due to the reaction to a stream of water more graphic.
1N22.51 reaction to a stream of water Tie one end of a 3' rubber hose to a spring and turn on the air, then cut the string.
1N22.90 computer plots of rocket motion Data from a Smart-pulley Atwoods machine with a funnel on one side is used to generate speed, position, and acceleration graphs.

30. Collisions in One Dimension

1N30.01 ref. coef. of restitution see 1R40.xx.
1N30.10 collision balls Two balls or many balls on bifilar suspension.
1N30.10 collision balls Six billiard balls are mounted on bifilar supports.
1N30.10 collision balls - croquet Weigh the balls at the store to get nearly equal masses.
1N30.10 collision balls Eleven billiard balls on bifilar suspension.
1N30.10 collision balls Two balls, five balls, six balls on bifilar suspension.
1N30.10 colliding balls Two balls of equal mass collide, then balls of various mass ratios are used. Collisions with a string of equal balls are also demonstrated.
1N30.11 bowling ball collision balls
1N30.11 bowling ball collision balls A large frame holds seven bowling balls on quadfilar supports.
1N30.12 collision balls Two balls on bifilar suspension.
1N30.13 collision balls A two ball collision ball apparatus for the overhead projector.
1N30.14 collision balls theory In addition to conservation of momentum and energy, the system must be capable of dispersion-free propagation.
1N30.14 collision balls - theory The collision balls are described as a series of spatially separated masspoints and springs with a force law exponent of 1.5.
1N30.15 pitfalls in rolling ball collisions Friction and other factors that affect rolling collisions.
1N30.15 billiard balls Do collision balls with billiard balls in a "v" track.
1N30.15 billiard balls A set of grooved billiard balls run on steel edges.
1N30.15 billiard balls Roll a ball down an incline into a trough with five other balls.
1N30.15 billiard balls Looks like a rolling bowling ball hits another.
1N30.16 billiard balls Duckpin balls slide on two taut parallel steel wires. Construction details in the appendix, p.566.
1N30.20 3:1 collision balls
1N30.20 collision balls - 3:1
1N30.20 collision balls, 3:1 A set of identical steel balls on bifilar suspensions. Also one ball can be three times the mass, insert wax for inelasticity.
1N30.20 3:1 collision balls Many collisions in a 3:1:1 system - elastic and inelastic.
1N30.21 collision balls, 3:1 Two ball collisions of pendula on bifilar supports. Elastic, inelastic, and 3:1 mass ratio. ref.APT,3,36,1935.
1N30.23 time reversal invariance The collisions of equal length pendula of different mass are used to demonstrate time reversal invariance. Also works with three balls.
1N30.25 impedance match collision balls
1N30.25 impedence match collision balls A big ball hits a smaller ball in one frame, and a second frame holds an series of balls between the big and small balls.
1N30.25 impedence match collision balls Big ball hits a small ball with and without an intermediate series of impedance matching balls.
1N30.25 impedence match collision balls First a large ball hits a small ball, then other various sized balls are interposed to maximize energy transfer.
1N30.29 collision balls analysis A simplified model of the collision balls that goes beyond conservation of energy and momentum but is still within the scope of an introductory course.
1N30.30 air track collision gliders
1N30.30 air track collision gliders Two sets of air track carts, one with springs and the other with velcro, give elastic and inelastic collision.
1N30.30 air trough collisions Elastic and inelastic collisions on the air trough. A circuit is given for a light beam gated oscillator for use with a scaler.
1N30.30 elastic and inelastic collisions Air gliders have springs on one end and the post/clay on the other.
1N30.31 air track collision tricks Place a meter stick on two carts and lift it up before one hits an end bumper, a simple spring release device momentarily held with beeswax.
1N30.31 air track collision gliders Use a meter stick resting on top of two airtrack carts to give equal velocities. After one hits the end bumper, you have equal and opposite velocities.
1N30.32 air track collision gliders A moving car runs into a stationary one and sticks. Photogate timing before and after.
1N30.33 equal and unequal mass air track collisions
1N30.33 air track collision gliders Air track carts with bumper springs.
1N30.33 air track collision gliders A small cart hits a big one elastically. The big one is placed so that after the collision both carts hit the ends simultaneously. The carts will again collide at the original place.
1N30.33 equal and unequal mass collisions Equal and unequal mass air gliders.
1N30.34 air track collision gliders Elastic and inelastic collisions on the air trough. A circuit is given for a light beam gated oscillator for use with a scaler.
1N30.36 hot wheels collisions Uses Hot Wheels.
1N30.41 inelastic collisions A simple student experiment for elastic and inelastic collisions using PSSC collision carts.
1N30.41 inelastic collisions A simple student experiment for inelastic collisions using PSSC collision carts.
1N30.43 inelastic collisions air cart clamp Design of a simple rubber clamp for stopping Ealing air carts.
1N30.43 inelastic collisions with clay Mount a plunger on one air track and a cylinder packed with modeling clay on the other.
1N30.43 inelastic collisons with velcro Mount velcro on air carts with Swingline paper binders.
1N30.43 inelastic collisions with velcro Use velcro instead of wax.
1N30.43 inelastic collisions Two latching carts that can be loaded come together with equal force. Construction details in appendix, p. 565.
1N30.45 velocity of a softball A softball is thrown into a box (inelastic collision) and the velocity of the box is obtained from the recoil distance.
1N30.46 slow inelastic collision An unrolling thread slowly transfers momentum between air track gliders.
1N30.50 bouncing dart
1N30.50 the bouncing dart Same as TPT 22(5),302.
1N30.50 the bouncing dart A dart hits a block of wood with a thud (inelastic) but with the pointer removed (elastic) knocks the block over showing greater impulse associated with elastic collisions.
1N30.51 ball - pendulum collisions A small ball rolls down an incline and strikes a larger pendulum bob on either a putty covered side or a plain steel side.
1N30.52 pendulum - cart collisions Two pendulums of equal height are released simultaneously from the same height so as to strike low friction carts. The pendulum bobs are of equal mass, one of steel and the other of clay. Greater momentum transfer during the elastic collision is observed.
1N30.55 elastic and inelastic model
1N30.55 elastic and inelastic model Two carts collide with a wall. One cart stops dead due to masses at oscillating inside with different frequencies.
1N30.60 double ball drop
1N30.60 double ball drop Drop a softball on a basketball.
1N30.60 dropping superballs Analysis of dropping two stacked superballs. Application to "slingshot effect" of space probes on the grand tour.
1N30.60 high bounce Drop a softball on a basketball (1:3) mass ratio.
1N30.61 double ball drop Some analysis of the double ball drop.
1N30.62 velocity amplification in collisions The complete treatment: double object, double ball, multiple ball, analog computer circuit, linear and non-linear models.
1N30.64 modified two ball drop A double mass-spring collision on a guide rod allows more control than the double ball method.
1N30.65 double air glider bounce
1N30.65 double air glider bounce Let two air gliders accelerate down 30 cm of track and measure the rebound as the mass of the lead glider is increased.
1N30.65 douple drop history Brief theory of the double ball drop. Suggests trying a double air cart collision on and inclined air track.
1N30.70 colliding cylinders One cylinder slides down a track and collides with another on a horizontal track. Friction is factored in.
1N30.71 modified colliding cylinders Modifications to AJP 42(1),54.
1N30.86 inelastic collisions photo A strobed photo is made of the collision of two carts on a table.
1N30.86 air track collision photo Record air track collisions with strobe photography.
1N30.87 air track collision timer Plans for an electronic device to be used for velocity readout in air track collision demonstrations. Gives readout before and after collision.

40. Collisions in Two Dimensions

1N40.10 shooting pool A framework allows a billiard ball pendulum to strike another on an adjustable tee.
1N40.11 orthogonal hammers Identical hammers hung at right angles hit a ball.
1N40.12 shooting pool An apparatus for recording collisions between ceiling mounted duckpin ball (5" dia.) and bowling ball (8 1/2" dia.).
1N40.13 shooting pool on the overhead Ink coated balls roll down chutes onto a stage placed on the overhead projector.
1N40.14 shooting pool A pool shooting box with a soapy glass surface and plans for a ball shooter.
1N40.16 shadow project collisions Vertically shadow project two dimensional collisions onto the floor. Much Discussion.
1N40.18 photograph golf ball collisions Suspend two golf balls from a ring that mounts on the camera lens and do a time lapse photo of the collision after one is pulled to the side and released.
1N40.18 photograph golf ball collisions The collision of two suspended golf balls is photographed.
1N40.20 air table collisions - equal mass
1N40.20 air table collisions
1N40.20 air table collisions (equal mass) Vary the angle of impact between a moving and stationary air puck. Lines are drawn on the screen.
1N40.21 air table collisions - unequal mass
1N40.21 air table collisions Use dry ice pucks to do two dimensional collisions.
1N40.21 air table collisions (unequal mass) Elastic collisions with unequal air pucks.
1N40.22 air table collisions - inelastic
1N40.22 air table collisions (inelastic) Inelastic collisions between equal and unequal mass air pucks.
1N40.24 air table collisions by video Use a video tape of the collision to obtain data.
1N40.24 air table collisions Use a spark timer to record collisions on an air table.
1N40.24 air puck collisions The path left by liquid air pucks on a table sprinkled with lycopodium powder show the 90 degree scattering law for particles of equal masses. Also a neutron diffusion demo. Construction details in appendix, p.570.
1N40.24 air table collisions Dry ice pucks with spark timer recording.
1N40.24 air table collisions photo Use strobe photography to record air table collisions.
1N40.25 lost momentum The air pucks are modified so the line of force during the collision passes through the center of mass.
1N40.30 nine-ball on the overhead, etc collisions with an array of three by three balls on the overhead projector. Also a four-ball two-dimensional coupled pendula suspension.
1N40.40 focusing collisions Balls are suspended from one string and spaced at a distance of 3r. Depending on the angle the collision is initiated, the collisions will either focus or defocus.
1N40.60 bouncing ball simulation An analog computer (circuit given) shows the path of a bouncing ball on an oscilloscope.
1N40.60 super ball bouncing Analysis of the trajectory of a super ball from the floor to the underside of a table and back to the hand.
1N40.90 computer collisions A FORTRAN program for collisions on a Tektronix 4012 graphics terminal and Honeywell DPS8 computer.

1Q ROTATIONAL DYNAMICS

10. Moment of Inertia

1Q10.10 inertia wands and two students Students twirl equal mass wands, one with the mass at the ends and the other with the mass at the middle.
1Q10.10 inertia wands and two students Give students equal mass wands to twirl, one with the mass at the ends and the other with the mass at the middle.
1Q10.10 inertia wands and two students Two apparently identical tubes, one with a mass concentration in the center, the other with a mass concentration at the ends.
1Q10.11 inertia wands Weights taped to meter sticks are used as low cost and visually obvious alternates to commercial apparatus.
1Q10.12 inertia rotator and two students Students rotate a "T" from a disc mounted on the bottom while holding the device by a sleeve. Weights are mounted at different distances on the cross bar.
1Q10.20 torsion pendulum inertia
1Q10.20 torsion pendulum inertia The period of a torsion pendulum is used to determine moment of inertia. Tinker toys allow one to easily construct objects with the same mass but different moments of inertia. Many variations are presented.
1Q10.20 torsion pendulum inertia Objects are placed on a trifilar supported torsional pendulum.
1Q10.20 torsion pendulum inertia Objects are added symmetrically about the torsional pendulum axis.
1Q10.20 torsion pendulum inertia Use the torsion pendulum to determine the moment of inertia.
1Q10.25 air bearing inertia Determine the ellipsoids of inertia of a rectangular steel bar with the air bearing supported rotating disc.
1Q10.25 air bearing inertia A steel triangle is dropped on an air bearing supported rotating disc.
1Q10.25 air bearing inertia Various objects are placed on an air bearing supported rotating disc.
1Q10.30 ring, disc, and sphere A ring, disc, and sphere of the same diameter are rolled down an incline.
1Q10.30 ring, disc, and sphere A ring, disc, and sphere of the same diameter are rolled down an incline.
1Q10.30 ring, disc, and sphere Rings, discs, and spheres are rolled down an incline.
1Q10.31 rolling bodies on incline
1Q10.31 rolling bodies on incline Rings, discs, spheres, and weighted discs are rolled down an incline.
1Q10.32 ring, disc Disc and ring on the incline plane.
1Q10.35 all discs roll the same
1Q10.35 all discs roll the same A set of discs of different diameters are rolled down an incline. Also use hoops and spheres.
1Q10.37 coffee can lab Rolling an empty coffee can down an incline. A student lab with many tasks.
1Q10.40 racing discs
1Q10.40 racing discs Two discs of identical mass, one weighted in the center and the other weighted at the rim, are rolled down an incline.
1Q10.40 racing discs Two wooden discs of the same mass and diameter are loaded with lead to give different moments of inertia. Roll on an incline.
1Q10.40 racing discs Two equal mass discs are made to race down an incline, one with a lead core and the other with a lead rim. Both are made to roll up a second incline to show they had the same kinetic energy at the bottom.
1Q10.41 moment of inertia spools Aluminum wheels are joined by two brass cylinders that can be placed at different radii to change the moment of inertia.
1Q10.50 racing soups
1Q10.50 racing soups Racing two soups first down an incline and then down and across the floor. Betting is used to make the demonstration more exciting.
1Q10.51 winning ball Use mercury filled rollers for sure winners.
1Q10.55 weary roller
1Q10.55 weary roller Load a roller with fine dry sand or powdered tungsten.
1Q10.56 viscosity A raw egg in a torsion pendulum damps more quickly than a boiled egg due to internal friction. Also spinning eggs - angular momentum.
1Q10.65 moment of inertia of a ball An air spinner for a 2" bronze ball and a method of mapping out the three axes of moment of inertia.
1Q10.66 errant pool balls Directions for making several different types of weird acting pool balls.
1Q10.70 rigid and non-rigid rollers
1Q10.70 rigid and non-rigid rotations Lead rings, the masses of a torsion pendulum, can be either locked or freed to show terms in Steiner's equation.
1Q10.70 rigid and non-rigid rotators Two lead rings are mounted as a torsion pendulum with rotational axes parallel to the pendulum. The period is measured with the rings freed and locked.
1Q10.70 rigid and non-rigid rotations Two masses on a horizontal bar fixed to a vertical shaft are spun by a falling weight. The masses can be locked or freed to rotate in the same plane as the vertical shaft.
1Q10.71 Steiner's theorem An adjustable double dumbbell on a rotating bar arrangement.
1Q10.75 parallel axis wheels The period of a bicycle wheel suspended as a pendulum is measured with the wheel spinning and locked.

20. Rotational Energy

1Q20.10 whirlybird (adj. ang. mom.) A weight on a string wrapped around a wheel drives a radial rod with adjustable weights.
1Q20.10 adjustable angular momentum A weight on a string wrapped around a wheel drives a radial rod with adjustable weights.
1Q20.10 adjustable angular momentum A weight wrapped around a wheel drives a radial bar with adjustable weights.
1Q20.10 adjustable angular momentum Hanging weights from three coaxial pulleys provides different applied torques to a radial bar with movable weights to provide adjustable moment of inertia.
1Q20.10 adjustable amgular momentum Two equal masses are mounted on a radial bar fixed to a horizontal axle with a pulley.
1Q20.10 angular acceleration machine A weight over a pulley turns a bar with adjustable weights. On screen timer and protractor helps measurements.
1Q20.12 adjustable angular momentum Hang various weights from the axle of a large wheel and time the fall.
1Q20.13 adjustable angular momemtum A horizontal bar mounted at its midpoint on a turntable has pegs for mounting weights at various distances, and is accelerated by a string to falling mass.
1Q20.14 adjustable angular momentum Spin the air bearing supported rotatable disc with a mass hanging on a string.
1Q20.15 flywheel and drum with wieght
1Q20.17 adjustable angular momentum A falling weight on a string wrapped around a spindle spins a variety of objects to show Newton's second law for angular motion.
1Q20.20 angular acceleration wheel
1Q20.20 angular acceleration wheel Measure the acceleration of a bike wheel with a mass on a string wrapped around the axle.
1Q20.20 bike wheel angular acceleration Measure the angular acceleration of a bike wheel due to the applied torque of a mass on a string wrapped around the axle.
1Q20.20 bike wheel angular acceleration Use a spring scale to apply a constant torque to a bike wheel and measure the angular acceleration.
1Q20.25 accelerate light and heavy pulleys
1Q20.25 accelerate light and heavy pulleys
1Q20.26 angular acceleration Use strobe photography to record the motion of a large disc accelerated by a mass on a string over a pulley.
1Q20.27 rotating dry ice puck A dropping mass on a string wrapped around a massive dry ice puck gives both linear and angular acceleration.
1Q20.28 rotational dynamics A dry ice puck with strings wrapped around two different radii going to equal masses hanging on opposite end of the table is stationary while a piece of masking tape is placed over one winding. Remove the tape and the puck spins and translates.
1Q20.30 rolling spool
1Q20.30 rolling spool A spool rolled down an incline on its axle and takes off when it reaches the bottom and rolls on its rim.
1Q20.30 rolling spool A large version of the rolling spool (16" dia.) is used as a lab. Construction hints and complete analysis.
1Q20.30 rolling spool A large spool is rolled down an incline on its small axle. When the outer discs reach the table, the thing takes off.
1Q20.30 rolling spool A spools rolls down a narrow incline on its axle. When it reaches the bottom, it rolls on the diameter of the outer discs.
1Q20.30 spool on incline A spool rolls down an incline on its central radius.
1Q20.31 rolling spool Place the rolling spool demonstration on a low friction sheet to show conservation of linear momentum as the sheet moves backward when the roller hits bottom.
1Q20.35 bike wheel on incline
1Q20.35 bike wheel on incline A bike wheel rolls down an incline on its axle with the axle pinned to the wheel or free.
1Q20.35 bike wheel on incline A bike wheel rolls down an incline on its axle. The wheel can be pinned to the axle.
1Q20.41 rolling up an incline A roller is timed as it rolls up an incline under the constant torque produced by a cord wrapped around over a pulley to a hanging mass.
1Q20.42 start a wheel Use a large DC motor and a large wheel to show the angular acceleration of a rotating body with a constant driving torque. Picture. Diagram.
1Q20.44 rolling pendulum A spherical bob can roll on a track of the same arc as its swing when suspended by a cord. Comparison of the motion in the two cases shows the effect of the rotational motion in rolling.
1Q20.46 radius of gyration (Here?) Slide an air cart down an inclined instrumented air track, then add a wood track and roll a ball down the same incline.
1Q20.47 spin a swing Wind up two balls on strings from a common support with a slack connecting string between them. As they unwind, the angular velocity decreases until the connecting string becomes taut, then increases. Ref: AJP 27, 611 (1959)
1Q20.50 faster than "g"
1Q20.50 faster than "g" A ball jumps from the end of a hinged stick into a cup as the stick rotates.
1Q20.50 faster then gravity A ball at the end of a falling stick jumps into a cup.
1Q20.50 falling chimney A hinged incline with a ball on the end jumps into a cup a few inches down the board as the incline drops.
1Q20.50 falling chimney Diagram. Ball on the end of a falling stick jumps into a cup attached near the end of the stick.
1Q20.50 falling chimney A ball on the end of a pivoting stick jumps into a cup. Includes TPT 3(7),323.
1Q20.50 hinged stick and ball A ball at the end of a hinged stick falls into a cup mounted on the stick.
1Q20.51 bowling ball faster than "g"
1Q20.51 bowling ball faster than "g" A bowling ball at the end of ten foot ladder jumps into a five gallon pail.
1Q20.52 faster than "g" - add mass Analysis of adding mass to the plank.
1Q20.52 falling chimney Use of a triangular board to increase R/I for the board. Analysis included.
1Q20.52 falling chimmey A mass can be added to the end of the bar to slow it down causing the ball to miss the cup.
1Q20.53 falling chimney Hinged beam falls with paint brushes at and off the center of mass record the motion of the two points.
1Q20.54 "faster than g" revisited An analysis three cases, one in which the particle catches up with the rod.
1Q20.54 free fall paradox Short derivation of the "faster than g" demonstration.
1Q20.55 pennies on a meter stick
1Q20.55 pennies on a meter stick Line a meter stick with pennies and drop one end with the other hinged. Happens to fast to see well. Use with the video.
1Q20.55 pennies on a meter stick A meter stick is loaded with pennies and held horizontally, then released at one end. Pennies on the first 2/3 stay with the stick.
1Q20.55 penny drop stick A horizontal meter stick, hinged at one end, is loaded with pennies and released.
1Q20.60 falling meter sticks - scaling
1Q20.60 falling meter sticks - scaling Compare the rate of fall of one meter and two meter sticks.

30. Transfer of Angular Momentum

1Q30.10 passing the wheel Pass a bicycle wheel back and forth to a person on a rotating stool.
1Q30.10 passing the wheel A bicycle wheel is passed back and forth to a person on a rotating stool.
1Q30.10 passing the wheel The lecturer on a rotating stool passes a spinning bike wheel back and forth to an assistant while turning it over.
1Q30.15 pass bags o' rice
1Q30.15 pass bags o' rice
1Q30.20 drop bags o' rice
1Q30.20 bags o' rice A person on a rotating stool holds out 10 lb bags of rice and drops them.
1Q30.25 satellite de rotator
1Q30.25 satellite derotator Same a disc 07-09.
1Q30.25 de-spin device Two heavy weights on cables are released from a vertically spinning disc to slow the system by conservation of angular momentum.
1Q30.25 de-spin device A mass flies out on a string satellite de-spin device with derivation of proper dimensions and weights.
1Q30.25 satellite derotator Heavy weights fly off a rotating disc carrying away angular momentum.
1Q30.30 catch the bag on the stool
1Q30.30 catch the bag on the stool Sit on the rotating stool and catch a heavy ball at arms length.
1Q30.30 catch the bag on the stool Throw or catch a bag of lead shot off axis while sitting on a rotating platform.
1Q30.30 catch the ball on the stool Baseballs or billiard balls may be thrown or caught at an arm's length by a demonstrator on a rotating stool.
1Q30.31 catch the ball on the stool Roll a ball down an incline and catch it off axis on the air bearing supported rotating disc.
1Q30.33 shoot ball at a shaft Shoot a steel ball at a catcher on the end of an arm that rotates.
1Q30.34 catch a ball on a rotating bar Roll a ball down an incline and catch it on the end of a modified Welch Centripetal Force Apparatus (No. 930) Similar to AJP 31,91 (1963).
1Q30.40 drop disc on rotating disc A second disc is dropped on an air bearing supported rotating disc. Spark timer recording.
1Q30.50 spinning funnel A funnel filled with sand spins faster as the sand runs out.
1Q30.50 spinning funnel A letter about TPT 22(6),391, "Demonstrating conservation of angular momentum".
1Q30.90 stick-propeller device The stick-propeller device appears to produce angular momentum from nowhere.

40. Conservation of Angular Momentu

1Q40.10 rotating stool and weights Spin on a rotating stool with a dumbell in each hand.
1Q40.10 rotating stool and dumbells A person on a rotating stool moves dumbbells out and in.
1Q40.10 rotating stool and dumbells Instructor stands on a rotating platform with a heavy dumbbell in each hand.
1Q40.10 rotating stool and dumbells Extend and retract your arms while rotating on a stool.
1Q40.10 rotating stool and dumbells Spin on a rotating stool with a dumbbell in each hand.
1Q40.10 rotating stool with weights A person sits on a rotating stool and moves weights in and out.
1Q40.11 big rotating stool and dumbells A cable pulley system moves large masses from 60 to 180 cm.
1Q40.12 rotating platform and dumbells Make a rotating platform out of two disks of 3/4" plywood and a large diameter thrust bearing.
1Q40.13 rotating stool Rotating platform made out of an auto front wheel bearing.
1Q40.15 rotating stool and long bar
1Q40.15 rotating stool and long bar Sit on a rotating stool holding a long bar with masses at the ends. Rotate the bar one way and you turn the other way.
1Q40.15 rotating stool and long bar Sit on the stool and hold a long bar with weights on the ends. Rotate the bar and you will move in the opposite sense.
1Q40.16 rotating stool and bat Stand on a rotating platform and swing a bat.
1Q40.16 rotating stool and bat Stand on a rotating stool and swing a baseball bat.
1Q40.20 squeezatron
1Q40.20 squeezatron A flyball governor can be expanded or contracted by squeezing a handle.
1Q40.20 rotating adjustable balls Plans for a two ball adjustable governor type conservation apparatus.
1Q40.20 squeezatron A flyball governor can be expanded or contracted by a squeeze handle.
1Q40.20 squeezatron Pulling a string decreases the radius of two masses rotating at the ends of a rod.
1Q40.20 squeezatron A mechanical device for showing the pirouette effect.
1Q40.21 dry ice puck rotators Two dry ice puck rotators: a) steel balls separate, b) they come together.
1Q40.23 centrifugal governor
1Q40.23 governors A small governor is spun on a hand crank rotator.
1Q40.23 Watt's regulator Use a model of Watt's regulator.
1Q40.23 govenors The Cenco Watt's governor shown with a valve regulating gear.
1Q40.23 centrifugal governor A model of a governor.
1Q40.25 pulling on the whirligig
1Q40.25 pulling on the whirligig Pull on the bottom ball of the whirligig.
1Q40.25 pulling on the whirlagig Balls are attached to either ends of a string that passes through a hollow tube. Set one ball twirling and pull on the other ball to change the radius.
1Q40.25 pulling on the whirlagig Shorten the string of a rotating ball on a string.
1Q40.26 pulling on the whirlagig A ball on a string rolls on the lecture table. In one case the cord wraps itself around a vertical rod. In the other, to cord is pulled through a hole in the table.
1Q40.30 rotating stool and bicycle wheel Invert a spinning bike wheel while sitting on a rotating stool.
1Q40.30 rotating stool and bicycle wheel A person sits on a rotating stool, spins a bicycle wheel and turns it over and back.
1Q40.30 rotating stool and bicycle wheel Inverting a spinning bicycle wheel while on a rotating stool, passing it back and forth.
1Q40.30 rotating stool and bicycle wheel Spin and turn a bike wheel while on a rotating stool.
1Q40.30 rotating stool and bicycle wheel Invert a spinning bike wheel while sitting on a rotating stool.
1Q40.31 stool, bicycle wheel, and friction Slow down the bike wheel deliberately to emphasize the role of friction in transfer of momentum.
1Q40.32 rotating stool and bicycle wheel Wrap the bicycle wheel with no. 9 iron wire.
1Q40.33 drop the cat Turn yourself around on a rotating stool by variation of moment of inertia. Also, make a model of a cat.
1Q40.34 skiing Go skiing while holding a bike wheel gyro. By conservation of angular momentum, turn yourself with the gyro.
1Q40.34 skiing Stand on a rotating turntable with skies on to show the upper part of the body turning opposite the lower.
1Q40.40 train on a circular track
1Q40.40 train on a circular track A HO gage train runs on a track mounted on a bike rim.
1Q40.40 angular momentum train A circular track on a rotating platform and a train have the same mass. The train and track move in opposite directions.
1Q40.40 angular momentum train A train on a rotating platform.
1Q40.40 train on a circular track A wind up train rides on a track mounted on the rim of a horizontal bicycle wheel.
1Q40.41 angular momentum train - air table The circular track is mounted on a large air table puck.
1Q40.42 frictional transfer of ang. momemtum Diagram. A balanced framework constrains a spinning wheel. As the wheel slows down, the framework begins to rotate.
1Q40.43 coupled windmills Picture. Two angular momentum machines (M-166) are coupled by a spring. The spring is wound and both are released simultaneously to show opposite reactions.
1Q40.44 counter spinning An induction motor is mounted so both the frame and armature can rotate freely. No torque is required to tilt the direction of axis of rotation unless either the frame or armature is constrained.
1Q40.45 wheel and brake
1Q40.45 noncoaxial rotating disks A battery driven turntable rotates noncoaxially on a frictionless turntable.
1Q40.45 wheel and brake A horizontal rotating bicycle wheel is braked to a large frame and the combined assembly rotates slower.
1Q40.50 pocket watch
1Q40.50 pocket watch A small pendulum is suspended from the stem on pocket watch placed on a small watch glass on a stand.
1Q40.50 pocket watch Suspend a pocket watch by its ring from a sharp edge.
1Q40.50 tail wags dog Use a laser to magnify the motion of a pocket watch.
1Q40.52 various demos You read this one.
1Q40.53 various demos A free system of two discs, one attached to a motor shaft and the other to the motor, is powered through slip rings. Show the discs rotate in opposite directions and come to rest at the same time.
1Q40.54 orbital angular momentum Apparatus Drawings Project No.33: A dumbbell pivoting on its center of mass, on a counterwieghted rod rotated about its center of mass, remains oriented in the original direction until friction prevails.
1Q40.55 buzz button Pull on a twisted loop of string threaded through a large button to get the thing to oscillate.
1Q40.55 buzz button A 6" wooden disc supported by a loop of string passing through two holes drilled 1/2" apart. Directions for showing constancy of axes.
1Q40.57 colliding air pucks The linear and angular momentum are recorded with strobed photography. The pucks have an arrow to indicate rotation.
1Q40.59 colliding spinning orbiting pucks One massive dry ice puck contains a motorized windlass that winds up a connecting string, the other has the string wound around it. One orbits, the other spins and when the come together they stop dead.
1Q40.60 sewer pipe pull
1Q40.60 sewer pipe pull Put "o" rings around a section of large PVC pipe to act as tires. Place on a sheet of paper and pull the paper out from under it.
1Q40.60 sewer pipe pull A newspaper is pulled out from under a large sewer pipe with O ring tires. When the paper is all the way out, the pipe stops dead.
1Q40.60 various demos Pull a strip of paper horizontally from under a rubber ball. As soon as the ball is off the strip, it stops dead.
1Q40.63 off-center flywheel A flat plate is free to rotate on a block of dry ice. The plate rotates about its center of mass when the flywheel at one end slows down.
1Q40.65 double flywheel rotator Two flywheels free to rotate about a vertical axis on a bar which is also free to rotate about a vertical axis are coupled in various ways to demonstrate "spin-spin" and "spin-orbit" coupling with and without dissipation.
1Q40.70 marbles and funnel
1Q40.70 marbles and funnel The angular speed of marbles increases as they approach the bottom of a large funnel.
1Q40.80 Hero's engine
1Q40.80 Hero's engine Similar to disc 15-07.
1Q40.80 Hero's engine Plans for a machine shop built Hero's engine.
1Q40.80 Hero's engine A model of Hero's engine.
1Q40.80 Hero's engine A simple Hero's engine made of a tin can.
1Q40.80 Hero's engine Cylindrical boiler pivots on a vertical axis with tangential pressure relief nozzles.
1Q40.80 Hero's engine A suspended round bottom flask with two nozzles.
1Q40.80 Hero's engine The flask rotates on a horizontal axis.
1Q40.81 Hero's engine - sprinkler A lawn sprinkler.
1Q40.81 Hero's engine - sprinkler A gravity head of water is used to drive a Hero's engine device (lawn sprinkler).
1Q40.82 air rotator with deflectors
1Q40.82 air rotator with deflectors Run an air sprinkler, then mount deflectors to reverse the jet.
1Q40.85 the Feynman inverse sprinkler A demonstration showing the inverse sprinkler moves in a direction opposite to that of a normal sprinkler.
1Q40.85 inverse sprinkler - kinematic study An extension of the AJP 57(7) article.
1Q40.85 the sprinkler problem A design for the sprinkler/inverse sprinkler and a lot of analysis.
1Q40.86 Hero's engine Place an air jet Hero's engine in a bell jar and pump out some air.
1Q40.87 inverse sprinkler demonstration An inverse sprinkler made of soda straw in a carboy exhibits no motion.
1Q40.88 inverse sprinkler - no rotation A conservation of angular momentum argument is invoked to show that no rotation will result in an inverse sprinkler.
1Q40.88 inverse sprinkler A letter full of opinions.
1Q40.88 inverse sprinkler letter reply The writer of the previous letter has comments "drawn from thin air", not unlike most of these little blurbs.

50. Gyros

1Q50.01 elementary explaination Precession explained using only Newton's laws.
1Q50.01 behavior of a real top Analysis of the behavior of a real top with a round end spinning on a surface with friction.
1Q50.01 analysis An elementary discussion of the gyroscope is presented. It is based on conservation of angular momentum and energy and does not require calculus.
1Q50.01 elementary analysis comment Comment on AJP 28(9),808.
1Q50.01 explaining top nutation The stability of torque-free rotations and top nutation without sophisticated mathematics.
1Q50.01 physical explaination Consider the rotation of two equal masses mounted on a frame of negligible mass. Also note that the mathematical simplification made in the study of rigid-body motion often tend to obscure what is happening.
1Q50.01 elementary analysis One approach to explaining the gyroscope in language familiar to the student.
1Q50.01 physical explaination Precession explained qualitatively without recourse to right-hand rules, torques, etc. A train track displacement demo is presented as an analog.
1Q50.01 physical explaination A simple physical explanation of precession.
1Q50.10 precessing disc Spin a cardboard disc on a pencil inserted in a hole at the center and touch a finger to the rim.
1Q50.10 precessing disc A phonograph record (or aluminum disc) is spun on a nail at the end of a wood dowel. Have the class predict which way the record will turn when touched with a finger.
1Q50.10 cardboard precession Spin a cardboard disc on a pencil inserted in a hole in the center and touch a finger to the rim.
1Q50.10 precessing disc A 6" aluminum disc on a long axial rod is hand spun to show precession due to gravitational torque.
1Q50.10 phonograph record A wood bar spinning in a horizontal plane on a pivot is tapped and the plane of rotation tips.
1Q50.10 phonograph record Spin a cardboard disc on a nail driven into the center into the end of a stick. Place a finger on the disc to cause it to precess.
1Q50.20 bicycle wheel gyro Spin a bicycle wheel mounted on a long axle with adjustable counterbalance.
1Q50.20 bicycle wheel gyro A small weighted bicycle wheel is mounted at the end of a long axle pivoted in the middle with an adjustable counterweight.
1Q50.20 bicycle wheel gyro The counterbalanced bicycle wheel gyro with clip-on vector arrows for the angular momentum and torque vectors.
1Q50.20 bicycle wheel gyro Spinning bike wheel mounted on an adjustable counterbalanced axle.
1Q50.20 bicycle wheel gyro A bicycle wheel is mounted on a long axle with adjustable counterbalance.
1Q50.20 bicycle gyro Drawings for making a very nice gyro out of a 24" bike wheel.
1Q50.20 bicycle wheel gyro Weigh one end of a bike wheel gyro axle while the gyro is hanging vertically, spinning while supported horizontally, and precessing about the scale.
1Q50.20 bicycle wheel gyro A bicycle wheel gyro with a slightly different setup.
1Q50.20 gyro with adjustable weights A small gyro is at the end of a pivoting rod with an adjustable counterweight.
1Q50.21 bike wheel on gimbals
1Q50.21 bicycle wheel gyro A spinning bike wheel with two handles is supported by a loop of string around one of the handles. Counterweights may be applied.
1Q50.22 suspended bike wheel A ball at one end of a bike wheel axle is placed into a socket on a bearing for demonstrating precession and nutation on a large scale.
1Q50.22 bike wheel turnaround Posts from a rotating platform support both ends of the axle of a bike wheel. One post is hinged so the wheel can be supported from one end only as the platform rotates.
1Q50.22 suspended bike wheel A bicycle wheel with handles is supported by loops of string tied to a crossbar that is hung by a single string. Push the ends of the handles horizontally in opposite directions.
1Q50.22 bike wheels on gimbals A bicycle wheel on gimbals has a long axle that can be weighted.
1Q50.23 bike wheel presession
1Q50.23 path of a rim point Photograph a flashing light attached to the rim of a spinning wheel during forced precession.
1Q50.23 bike wheel precession A spinning bicycle wheel is supported by a rope at one end of a long axle.
1Q50.24 walking the wheel
1Q50.24 walking the wheel A spinning bicycle on a short axle dangles from a string held in the hand. Try to apply a torque that will bring the axle to a horizontal position.
1Q50.24 walking the wheel A spinning bike wheel is mounted on one end of an axle and the other end has a loop of string. Try to get the bike wheel in the vertical position by applying a torque to the string.
1Q50.25 double bike wheel gyro
1Q50.25 double bike wheel gyro Two bike wheel are mounted coaxially. Try the standard demos with the wheels rotating in the same direction and in opposite directions.
1Q50.25 double bike wheel gyro Do the standard single bike wheel demos with two coaxial bike wheels counter rotating.
1Q50.25 double bike wheel gyro Two bike wheels are mounted on the same axle. The standard demos are done with the wheels rotating in the same and opposite directions.
1Q50.25 double bike wheel The double bike wheel gyro precesses when both wheels rotate in the same direction. Has a nonstandard mount.
1Q50.26 inverted bike Three demos involving bike wheel demos, one of which is a double wheel device.
1Q50.30 MITAC gyro
1Q50.30 MITAC gyro A commercial motorized gyro on gimbals.
1Q50.30 MITAC gyro Evaluation of the MITAC gyro. Paint the gimbals as suggested by AJP 14,116 (1946).
1Q50.30 MITAC gyro A commercially built motorized gyro on a gimbal includes counterweights.
1Q50.30 motorized gyroscope A motorized gyro in gimbals.
1Q50.31 ride a gyro
1Q50.31 ride a gyro Same as AJP 56(7),657.
1Q50.31 a large gyro Make a gyro out of an auto wheel and tire. This is big enough to sit on.
1Q50.35 gyro in gimbals
1Q50.35 gyro in gimbals Push a cart with a gyro around the room.
1Q50.35 gyro on turntable A gyro set in gimbals is carried around.
1Q50.35 gyroscopic stability Move a gyro mounted on gimbals.
1Q50.40 suitcase gyro
1Q50.40 suitcase gyro Spin up a flywheel hidden in a suitcase and have a student turn around with it.
1Q50.40 suitcase gyro A battery powered motor runs a flywheel in a suitcase.
1Q50.40 suitcase gyro A large gyro is mounted in a suitcase.
1Q50.41 feel of a gyro Hold a heavy gyro outfitted with good handles.
1Q50.42 various gyros pictures of various gyros.
1Q50.43 magnetic gyro Two magnetic gyros.
1Q50.45 air bearing gyro
1Q50.45 air bearing gyro A large air support for a bowling ball.
1Q50.45 air bearing gyro Shop drawings and construction hints for making a air bearing for a 4" diameter ball.
1Q50.45 air bearing gyro Apparatus Drawings Project No.3: Air suspension gyro for a hardened steel ball bearing. Designed for use lab.
1Q50.45 air bearing gyros A bowling ball air gyro spins for a half hour when spun by hand. The uneven weight distribution produces precession. Also shows a 4" steel ball bearing air gyro.
1Q50.45 air bearing gyro Directions for making an air bearing for a bowling ball.
1Q50.45 air bearing gyro The air bearing gyro. Construction details in appendix, p. 587.
1Q50.45 air-bearing gyro A large air bearing gyro has a long horizontal shaft with arrow heads for visual emphasis.
1Q50.45 air bearing gyro Small mirrors on an air bearing gyro are used to demonstrate instantaneous axis of rotation, angular momentum vector, etc.
1Q50.50 precession with quality gyro A high quality gyroscope with a counterweight is used to show the fundamental precession equation with fair precesion.
1Q50.51 precession A model shows precessing axes.
1Q50.52 instantaneous axis A bicycle wheel is pivoted at the center of mass and has a disc mounted above the wheel in a parallel plane. The instantaneous axis can be seen as the point of no motion on the upper disc.
1Q50.53 precession of the equinoxes A rubber band provides a torque to a gyro framework hanging from a string causing precession.
1Q50.54 precessing earth model A fairly complex gyroscope.
1Q50.55 wobbly earth Add abstract in Handbook.FM
1Q50.56 precessing ball A ball placed on a rotating table precesses about the vertical axis with a period 7/2 of the table.
1Q50.57 Kollergang A device induces precession and change of weight is noted.
1Q50.58 nutations A vertical gimbal mounted shaft has a gyro on the bottom end and a light bulb and lens on the top. Nutations of the gyro are shown by the moving spot of light on the ceiling.
1Q50.59 motorcycle as a gyro The handlebars are twisted (but not moved) in the direction opposite to the turn to lay the machine over.
1Q50.59 tip a bike wheel A bike wheel on a front fork is hand spun and tipped to one side.
1Q50.60 gyrocompass
1Q50.60 gyro on turntable A gyro in a gimbal sits on a rotating table. Remove the degree of freedom about the vertical axis and the gyro will flip as the table is reversed.
1Q50.60 2 degrees of freedom Spin flip on turning a restricted gyroscope.
1Q50.60 gyrocompass A gyroscope in gimbals is deprived of one degree of freedom. A slight change of direction will cause a spin flip.
1Q50.61 gyrocompass Shows the origin of the error of an uncorrected gyrocompass.
1Q50.62 airplane turn indicator Diagram. Model of an airplane turn indicator in which the gyro precesses about the axis of the fuselage.
1Q50.63 gyrocompass A model of a gyrocompass for any latitude on the spinning earth.
1Q50.70 stable gyros
1Q50.70 stable gyros A gyro on a ladder will become stable when spinning.
1Q50.71 stable gyro car A spinning gyro mounted on a two wheel cart rides a stretched wire.
1Q50.71 stable gyro A very clever gyro "rider" on a model bike.
1Q50.71 stable gyro monorail car A monorail car stabilized by a gyro.
1Q50.72 ship stabilizer
1Q50.72 ship stabilizer Model of a ship stabilizer.
1Q50.72 ship stabilizer A large boat model you can sit in with a motor driven gyroscope.
1Q50.72 ship stabilizer A motorized gyro is free to turn on a vertical axis when the ship model is rocked.
1Q50.73 gyro on stilts A top-heavy gyro on stilts teeters about its position of unstable equilibrium.
1Q50.74 trapeze gyros A gyro on a trapeze is stable only when spinning.
1Q50.74 trapeze gyros Gyro on a trapeze shows stability when there are two degrees of freedom.
1Q50.74 trapeze gyros Gyro on a trapeze.
1Q50.75 ganged gyros Ganged gyros are spun in the same or opposite directions.
1Q50.76 gyro damped pendulum Picture. Frictional torque can be applied to the precession axis to damp the motion of the pendulum.
1Q50.80 gyro pendulum A gyroscope is hung from one end of its spin axle by a string and is swung as a pendulum.
1Q50.90 Maxwell's gyro The extended shaft of a gyro supported at its center of mass will trace out complex contours.
1Q50.90 Maxwell's gyro The spindle of a heavy spinning wheel pivoted at its center of gravity will follow an irregularly shaped object.
1Q50.90 walking gyro An apparatus for walking a gyroscope along a cradle.
1Q50.95 air bearing Maxwell's top Plans for an air bearing Maxwell's top resting on a 2" dia ball with matching air bearing cup with tangential air jets to provide torque.
1Q50.99 gyroscope accelerator A six inch wheel from a child's wagon in a 1/4" drill is used to spin up a gyroscope.

60. Rotational Stability

1Q60.10 bicycle wheel top Extend the axle of a weighted bike wheel and terminate with a rubber ball.
1Q60.10 bike wheel top Extend the axle of a weighted bike wheel and terminate with a rubber ball.
1Q60.15 humming top
1Q60.15 humming top The standard toy top that you pump up.
1Q60.15 yo-yo top Description of an antique toy demonstrating various aspects of rigid body rotational motion. Several pictures should make it possible to duplicate the thing.
1Q60.16 old fashioned top An old fashioned top that you throw with a string.
1Q60.18 gyro gun A shell is spun by hand before being fired by a gun.
1Q60.25 spinning coin An analysis of "wobbling", exhibited by common objects (coins, bottles, plates, etc) when they are spun on horizontal, flat surfaces. The apparatus maintains "wobbling" motion of a metal cylinder, which can be observed in slow motion by means of stroboscopic illumination.
1Q60.30 tippe top
1Q60.30 tippe top The tippe top.
1Q60.30 tippe top A tippe top was spun on smoked glass. Photos show the path of the stem until flip and the soot marks on the top.
1Q60.30 tippe top A brief review of the history of the tippe top problem.
1Q60.30 tippe top The tippe top flips when spun.
1Q60.30 tippe top Show that the tippe top spins in the opposite of the expected direction when inverted.
1Q60.30 tippy top The tippe top flips.
1Q60.31 tippe top analysis Physical arguments are presented which support the convention that the influence of sliding friction is the key to the understanding of the top's behavior. A rigorous analysis of the top's mechanics is offered, together with computer-generated solutions of the equations of motion.
1Q60.35 spinning football
1Q60.35 spinning football Spin a football and it raises up on end.
1Q60.35 spinning football Spin a football on its side.
1Q60.35 spinning football Spin a football and it rises onto its pointed end.
1Q60.35 spinning football An iron slug cut in the shape of a football is put on a magnetic stirrer.
1Q60.35 football spin Spin a football on its side and it will rise up on its end.
1Q60.36 spinning L'Eggs Instead of hard and soft boiled eggs, fill L'Eggs with water, paraffin, or air. Instructions and a little analysis are included. On a separate subject, a hint to use an egg instead of a ball in the floating ball demo.
1Q60.36 spinning egg Try the spinning egg demo with eggs boiled for different lengths of time.
1Q60.36 spinning eggs, etc. Positional stability of various shaped objects.
1Q60.37 billiard ball ellipsoid
1Q60.37 billiard ball ellipsoid Same as AJP 44(11),1080.
1Q60.37 billiard ball elipsoid A billiard ball on an air bearing shows the spectacular motion of free rotating rigid and semirigid bodies moving near their inertial singularities. Or, the billiard ball on an air bearing acts goofy when you spin it in certain ways.
1Q60.37 billiard ball ellipsiod A billiard ball weighted with brass rods along orthogonal axes will show spin flip.
1Q60.40 tossing the book
1Q60.40 tossing the book Throw a book or board up in the air spinning it about its three principle axes.
1Q60.40 tossing the book Directions of constructing blocks of inhomogeneous mass distribution for use in demonstrating the intermediate-axis theorem.
1Q60.40 tossing the book, etc A simple method of measuring the moments of inertia about the three axes before tossing the book. Also has a simple straw and paperclip inertia wand.
1Q60.40 tossing the book A board of unequal dimensions is tossed and spins about various axes.
1Q60.40 tossing the book Toss a 8x4x1 block into the air.
1Q60.40 stable and unstable axes of rotation Toss a rectangular board into the air.
1Q60.45 tossing the hammer
1Q60.45 tossing the hammer
1Q60.46 the hammer flip simplified An explanation of the hammer flip using only the concept of centrifugal force in a rotating reference frame.
1Q60.50 spinning lariat, hoop, and disc
1Q60.50 spinning lariet, etc. A rod, hoop, and flexible chain are attached to a hand drill.
1Q60.50 spinning lariet A hand drill held vertically is used to rotate loops of rope or chain.
1Q60.50 spinning lariet A loop of flexible chain is attached to a hand drill.
1Q60.51 spinning rod and hoop
1Q60.51 spinning lariet, hoop, and disc A hoop and disc suspended from the edge are spun with a hand drill until they each stability.
1Q60.51 spinning rod and hoop of wire Spin a hoop and long rod with a drill.
1Q60.52 spinning lariet, bar A bar is hung from one end by a string on a hand drill. When spun, the bar will rise. Also spin a loop of chain.
1Q60.53 spinning box A rectangular box rotated from a chain around any of the three principle axes will rotate about the axis of maximum rotational inertia.
1Q60.54 rotating vertical chain The five stable patterns observed in a vertical rotating chain are used to introduce Bessel's function.
1Q60.56 spinning bifilar pendula A variable speed motor drives a horizontal rod in a horizontal plane with bifilar pendula of different lengths attached.
1Q60.70 orbital stability Identical masses slide out on a horizontally rotating crossarm both attached to the same central hanging mass.
1Q60.71 quadric restoring force A leaf spring provides a quadratic restoring force to dumbbells rotating on a crossarm. Each angular velocity corresponds to only one stable orbit.
1Q60.72 rotational instability Different springs will result in conservation of angular momentum or instability in a spring loaded dumbbell.
1Q60.73 linear restoring force Two dumbbells slide out as a crossarm rotates with a spring providing the restoring force. At the critical angular velocity the orbits are stable at any radius.
1Q60.80 static/dynamic balance
1Q60.80 static/dynamic balance Same as disc 07-15.
1Q60.80 static/dynamic balance A rotating system suspended by springs shows both the difference between static and dynamic balance.
1Q60.81 dynamic tire balancing Analysis of dynamically balanced wheels shows they must also be statically balanced.
1Q60.90 Marion's dumbell A simple apparatus to demonstrate the non-colinearity of the angular velocity vector and the angular momentum vector. Helps students increase their understanding of angular velocity, angular momentum, and the inertial tensor. Theory and construction details.

1R PROPERTIES OF MATTER

10. Hooke's Law

1R10.10 stretching a spring Add masses to a pan balance and measure the deflection with a cathetometer.
1R10.10 stretching a spring Add masses to a pan balance and measure the deflection with a cathetometer.
1R10.10 stretching a spring Examining the force-displacement curve at small extensions.
1R10.10 Hooke's law Add 10, 20, and 30 newtons to a large spring.
1R10.20 strain gauge
1R10.20 strain gauge A spring attached to a Pasco dynamic force transducer is pulled to various lengths. Display the resulting force on a voltmeter.
1R10.25 pull on a horizontal spring
1R10.25 pull on a horizontal spring Pull on a horizontal spring with a spring scale.
1R10.30 springs in series and parallel Pull on a spring, springs in series, and springs in parallel with a spring scale. Compare the force required to stretch each case 60 cm.
1R10.30 springs in series and parallel Add abstract in Handbook.FM

20. Tensile and Compressive Stress

1R20.10 breaking wire Add weights to baling wire attached to the ceiling until the wire breaks.
1R20.10 breaking wire Add heavy masses to a thin copper wire until the wire breaks.
1R20.10 breaking wire Add weights to baling wire attached to the ceiling until the wire breaks.
1R20.10 breaking wire Contains several hints about stretching wires.
1R20.11 elastic limits
1R20.11 elastic limits Stretch springs of copper and brass. The copper spring remains extended.
1R20.12 breaking wire support Drill a hole axially up a 1/4" eye hook and solder the wire in.
1R20.15 Young's modulus
1R20.15 Young's modulus Hang weights from a wire. Use a laser and mirror optical lever to display the deflection.
1R20.18 Poisson's ratio A rubber hose is stretched to show lateral contraction with increasing length.
1R20.20 bending beam
1R20.20 bending beam Ten lbs. is hung from the center of a meter stick supported at the ends. Orient the meter stick on edge and then on the flat.
1R20.20 rectangular bar under stress A rectangular cross section bar is loaded in the middle while resting on narrow and broad faces.
1R20.20 bending the meter stick Some techniques for making the amount of bending visible to the class.
1R20.20 bending beams Hang weights at the ends of extended beams. Use beams of different lengths and cross sections.
1R20.25 sagging board
1R20.25 sagging board Place the ends of a thin board on blocks, then add mass to the center.
1R20.27 aluminum/steel elasticity paradox Copper and brass rods sag different amounts under their own weight but steel and aluminum do not.
1R20.31 stretch a hole Holes arranged circle in a rubber sheet deform into an ellipse when stretched.
1R20.32 deformation under stress A pattern is painted on a sheet of rubber and deformed by pulling on opposite sides.
1R20.38 stress on a brass ring A strain gauge bridge is used to measure the forces required to deform a brass ring. Diagram. Construction details.
1R20.39 squeeze the bottle Fill a whisky flask with a stopper and a small bore tube. Squeeze the bottle and watch the colored water rise in the tube.
1R20.40 buckling tubes
1R20.60 Bologna bottles
1R20.60 bologna bottles Carborundum and bologna bottles.
1R20.60 bologna bottle Pound a nail with a Bologna bottle, then add a carborundum crystal to shatter the bottle.
1R20.70 Prince Rupert's drops
1R20.70 Prince Rupert's drops Prince Rupert's drops.
1R20.70 Prince Rupert's drops Drops of glass cooled quickly can be hit with a hammer but shatter when the tip is broken off.
1R20.70 Prince Rupert's drops Prince Rupert's drops.

30. Shear Stress

1R30.10 shear book
1R30.10 shear book Use a thick book to show shear.
1R30.10 shear book Use a very thick book to demonstrate shear.
1R30.10 shear block Stacks of cards or a big book.
1R30.20 foam block
1R30.20 foam block Push on the top of a large foam block to show shear.
1R30.20 foam block Nice pictures of a foam block for sheer demonstrations.
1R30.20 foam block A large sponge is used to show shear.
1R30.20 foam block Use a rectangular block of rubber.
1R30.30 spring cube
1R30.30 spring cube A 3x3x3 cube of cork balls is held together with springs.
1R30.30 spring cube A cube of 27 cork balls fastened together with springs.
1R30.31 plywood sheets A stack of plywood sheets with springs at the corners is used to show shear, torsion, bending, etc. Diagram.
1R30.35 shear and stress modulus Unsophisticated apparatus for measuring elastic constants of a thin flexible strip and rod.
1R30.40 torsion rod
1R30.40 torsion rod
1R30.40 modulus of rigidity A rod is twisted by a mass hanging off the edge of a wheel.
1R30.40 bending and twisting Wind a copper strip around a rod and then remove the rod and pull the strip straight to show twisting.
1R30.40 torsion rod Rods of various materials and diameters are twisted in a torsion lathe.
1R30.45 shear and twist in screw dislocation Rule a thick walled vacuum tube with a grid, slit lengthwise, and dislocate one unit.

40. Coefficient of Restitution

1R40.10 bouncing balls
1R40.10 bouncing balls Drop balls of different material on a tool steel plate.
1R40.10 bouncing balls Balls of various materials are bounced off plates of various materials.
1R40.10 bouncing ball Loss of mechanical energy in the coefficient of restitution.
1R40.10 bouncing balls Drop balls on a glass plate.
1R40.10 coefficient of restitution Drop glass, steel, rubber, brass, and lead balls onto a steel plate.
1R40.11 bouncing balls An eight inch or larger reflecting telescope mirror blank provides a concave surface for bouncing balls.
1R40.11 coefficient of restitution Drop a small ball bearing on a concave lens.
1R40.12 coefficient of restitution Rubber balls of differing elasticity and silly putty are dropped in a tube onto a steel surface.
1R40.13 coef. of restitution in baseballs Analysis leading to a prediction of up to 15 foot difference in long fly balls due to variation in coefficient of restitution.
1R40.30 dead and live balls Drop bounce and no-bounce balls.
1R40.30 dead and live balls Drop bounce and no-bounce balls.
1R40.30 dead and live balls Drop a black super ball and a ball rolled from apiezon wax.
1R40.31 dead ball A non-bounce ball: fill a hollow sphere with iron filings or tungsten powder.

50. Crystal Structure

1R50.10 solid shapes How to make solid tetrahedrons and octahedrons.
1R50.15 solid models Styrofoam balls and steel ball bearings are used to make crystal models.
1R50.16 sphere packing Balls are stacked on vertical rods mounted on a board to build various crystal structures. Diagram.
1R50.17 Moduledra crystal models Tetrahedral and octahedral building blocks are used to construct a large variety of crystal shapes. Many pictures.
1R50.18 elastic crystal models Crystal models are built with a combination of compression and tension springs.
1R50.20 crystal models
1R50.20 crystal models
1R50.20 crystal lattice models Have many crystal lattice models available.
1R50.20 crystal models Show lattice models of sodium chloride, calcium carbonate, graphite, and diamond.
1R50.21 ice model How to make ball and stick water molecules that can be stuck together to make ice.
1R50.22 tennis ball crystals Old tennis balls glued together to give two close packed crystals.
1R50.25 Poisson contraction model A two dimensional spring model to show Poisson contraction in crystals.
1R50.29 crystal overlays Colored overlays of crystal structure for use on the overhead projector. Picture.
1R50.30 crystal structure Show natural crystals of salt, quartz, and other minerals, and lantern slides of snow crystals.
1R50.31 crystal growth from melt Several organic compounds produce good crystals from melts on microscope slides.
1R50.31 crystal growth in a film Crystal growth on a freezing soap film is observed through crossed Polaroids
1R50.31 ice nuclei Large ice crystals form on the surface of a supercooled saturated sugar solution.
1R50.32 make tin crystal Pour pure tin into a Pyrex mold, other steps.
1R50.40 crystal fault model
1R50.40 array of spheres Prepare a slide with a monolayer of 2.68 micron diameter polymer spheres that exhibits grain boundaries, extended dislocations, etc.
1R50.40 stacking fault model A closest packing spheres model that demonstrates a fault going from fcc to hcp.
1R50.40 crystal faults One layer of small ball bearings between two Lucite sides.
1R50.40 faults in crystal Show natural faults in a calcite crystal, then the single layer of small spheres model.
1R50.42 deformation front model A water film evaporating from an array of mesas shows the film edge pinned at several locations.
1R50.45 crushing salt
1R50.45 crushing salt Crush a large salt crystal in a big clamp.
1R50.45 crushing salt A large salt crystal is crushed in a "c" clamp.