[:PiraScheme#Mechanics: Table of Mechanics]

[:WorkEnergy: Mechanics (1M): Work and Energy]

[:RotationalDynamics: Mechanics (1Q): Rotational Dynamics]

[:Demonstrations:Lecture Demonstrations]

Grayed out demonstrations are not available or within our archive and are under consideration to be added.

PIRA #

Demonstration Name

Abstract

1N10.10

Collision Time Pendulum

Two metal wire bifilar pendulums 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

Throw a silicone ball at a dirty blackboard, measure the diameter of it's imprint. Then, place weights on the silicone ball until it deforms to the same diameter as the imprint. 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.

1N10.25

Drop Egg in Water

It doesn't break.

1N10.30

Pile Driver with Foam Rubber

Break a bar of plexiglass or sheet supported on two blocks with a pile driver. Add foam rubber to a second bar or sheet and it doesn't break.

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 Safety 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

Show segments of the video disc.

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 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.

1N10.70

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.

1N10.74

Model Rocket Thrust

An apparatus designed to measure the thrust of a rocket is used to check the manufacturer's specifications.

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 Pendulum Independent of Medium

A rocket pendulum maintains the same angle of recoil in air or water showing thrust is independent of medium.

PIRA #

Demonstration Name

Abstract

1N20.10

Seesaw Center of Mass

A string holding two carts with opposing horseshoe magnets is burned and they remain balanced on a board as they repel. The carts can be loaded unequally.

1N20.12

Rolling Ball on Air Cart

A ball rolls down a small inclined plane mounted on an air track glider. Watch the glider start and stop.

1N20.15

Train on 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 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 Air Track

An HO gauge train and 36" track mounted on a air cart. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS00003300001000085700000|1&idtype=cvips&doi=10.1119/1.1971014&prog=normal AJP 33(10), 857].

1N20.20

Spring Apart Air Track Gliders

Burn a string holding a compressed spring between two air gliders of unequal mass.

1N20.21

Reaction Carts with Lights

Two carts of equal mass sit in the center of an air track. Then, they are accelerated away from one another by magnets, explosives, springs etc. Because the carts are of the same mass, given the same velocity, and begin in the middle of the track, they reach the ends of the track at the same time. A photogate or some other mechanism signals their arival by lighting a light bulb.

1N20.24

Recoiling Magnets

Hold two small horseshoe magnets together on an overhead projector and observe the recoil.

1N20.25

Elastic band Reaction Cars

Pull apart two carts of unequal mass attached to each other with an elastic band. They accelerate toward one another.

1N20.30

Exploding Pendulums

Two large pendulums of unequal mass are held together compressing a spring. When the spring is released, two students mark the maximums.

1N20.32

Exploding basketballs

Explode a firecracker between a light and heavy basketball that are suspended near the ceiling. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000041000007000922000001&idtype=cvips&doi=10.1119/1.1987419&prog=normal AJP 41(7),922].

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. The center of mass may move a noticeable amount due to friction. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000034000008000707000002&idtype=cvips&doi=10.1119/1.1973407&prog=normal AJP 34(8), 707] for the demo and [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000035000004000359000001&idtype=cvips&doi=10.1119/1.1974087&prog=normal AJP 35(4), 359] for a comment about friction.

1N20.60

Air Track Center of Mass Collision

An inelastic air track collision with a cart and a spring coupled cart system. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000057000002000182000001&idtype=cvips&doi=10.1119/1.16092&prog=normal AJP 57(2), 182].

PIRA #

Demonstration Name

Abstract

1N21.10

Floor Carts and Medicine Ball

Two people on roller carts throw a medicine ball to each other or to at the wall.

1N21.20

Catapult from Cart to Cart

Catapult a ball from one cart to another. The ball needs to be quite heavy and the carts need low friction wheels.

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.

1N21.30

Ballistic Air Glider

Shoot a .22 into a wood block mounted on an air glider. Use a timer to determine the velocity. See the [http://groups.physics.umn.edu/demo/old_page/demo_gifs/1N21_30.GIF University of Minnesota website].

1N21.40

Drop Mass on Cart

A cart passes by a device that adds mass to the cart. Timers measure the velocity before and after the transfer.

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.

PIRA #

Demonstration Name

Abstract

1N22.01

historical note

An article claims rockets will not work in space because there is nothing to push against.

1N22.10

[:CO2ExtinguisherRocket: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 video

Show video of a rocket or shuttle launch.

1N22.20

[:WaterRocket: Water Rocket]

Pump a toy water rocket the same number of times, first with only air, and then with water.

1N22.23

air track rocket

Air from a rubber balloon propels an air cart.

1N22.25

balloon rocket

"Balloon rockets" are available at toy stores. Normal balloons follow more random paths.

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

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

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.

1N22.60

[:EthanolRocket: Ethanol Alcohol Rocket]

1N22.90

computer plots of rocket motion Data from a Smart-pulley

Atwood's machine with a funnel on one side is used to generate speed, position, and acceleration graphs.

PIRA #

Demonstration Name

Abstract

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

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 mass points 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

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

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

impedance match collision balls

Big ball hits a small ball with and without an intermediate series of impedance matching balls.

1N30.25

impedance 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

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

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 collisions 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

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

Two carts collide with a wall. One cart stops dead due to masses at oscillating inside with different frequencies.

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

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

double 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.

PIRA #

Demonstration Name

Abstract

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)

Vary the angle of impact between a moving and stationary air puck. Lines are drawn on the screen.

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)

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.