[:PiraScheme#Mechanics: Table of Mechanics]

[:Newtons1STLaw: Mechanics (1F): Newton's First Law]

[:Newtons3RDLaw: Mechanics (1H): Newton's Third Law]

[:Demonstrations:Lecture Demonstrations]

PIRA #

Demonstration Name

Abstract

1M10.10

shelf and block Lift a block up and set it on a shelf.

1M10.15

block on table

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 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.

PIRA #

Demonstration Name

Abstract

1M20.01

simple machines

A collection of simple machines is shown.

1M20.10

pulleys

An assortment of large pulleys can be rigged several ways.

1M20.10

pulleys

Demonstrate what you have.

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

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

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

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 counterweight 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

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

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.

PIRA #

Demonstration Name

Abstract

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.acceleration 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.

PIRA #

Demonstration Name

Abstract

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 rolls 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

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

A ball can escape the energy well when released from a point above the peak of the opposite side.

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

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

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

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

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

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- 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

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

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

Measure the height of recoil on an air cart glider on an incline after compressing a spring different to different lengths.

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

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

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

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

ratchet 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.

1M40.76

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.

1M40.91

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.

PIRA #

Demonstration Name

Abstract

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