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||1M40.50||Big Yo-Yo: Maxwell's 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||[:YoYo:Maxwell's Yo-Yo]||A large disc is suspended from a small axle so the string unwinds on the way down and rewinds on the way up showing that rotational energy is conserved.||

[:PiraScheme#Mechanics: Table of Mechanics]

[:Gravity: Mechanics (1L): Gravity]

[:Linear_Momentum: Mechanics (1N): Linear Momentum]

[:Demonstrations:Lecture Demonstrations]

Work and Energy

PIRA classification 1M

51 Demonstrations listed of which 25 are grayed out

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


1M10. Work


Demonstration Name



Shelf and Block

Lift a block up and set it on a shelf. (Work.)


Carry a Block

Just carry a block around. (No work.)


Pile Driver - Model

Drive a nail into a block of wood with a model pile driver. Use a 1kg mass guided by a 2 ft. clear plexiglass tube in which the mass fits loosely. A string is be used to pull it back up. See [http://physicslearning.colorado.edu/PIRA/Sutton/PARTI.pdf#pagemode=none&page=1 Sutton M-133].


Pile Driver

A massive weight (approx. 30 lbs.) is lifted in a frame to a height of about 10 ft. and dropped onto a landscaping spike on a railroad tie.


Pile Driver with Soda Cans

Smash pop cans with a pile driver.


Work to Remove Tape

Pull off a piece of tape stuck to the lecture bench.


1M20. Simple Machines


Demonstration Name



Simple Machines

A collection of simple toy machines.


[:BlockNTackle: Block and Tackle Pulley Systems and Pulley Advantage]

An assortment of large pulleys are rigged several ways.


Mechanical Advantage of Pulleys

Hang a 10N weight on a string passing over a pulley and measure the force with a spring scale, then hang the weight from a pulley that is free to move up and down.


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.


Bosun's Chair

Using a block and tackle, the lecturer ascends. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000044000009000882000001&idtype=cvips&doi=10.1119/1.10288&prog=normal AJP 44(9), 882].


Monkey and Bananas

A yo-yo and counterweight are suspended over a pulley. The counterweight and yo-yo rise and fall.



A model windlass is described.


Climbing Pirate

String is wrapped around two different sized pulleys on a common axis.


Big Screw

A large wood screw and nut show the relationship between a screw and incline.



A torque bar, spring scale, and pivot are used to illustrate the three classes of levers.


1M30. Non-Conservative Forces


Demonstration Name



Air Track Collisions / Sliding Masses

Compare the bounce of an air cart on an inclined air track with a mass that is attached tightly and loosely. A Pasco car and track can be used as well


Negative Acceleration Due to Friction

A pendulum hits a tabletop, transferring a wood block rider to the tabletop. Potential to kinetic energy is depleted due to friction. See [http://physicslearning.colorado.edu/PIRA/Sutton/PARTI.pdf#pagemode=none&page=1 Sutton M-109].


The Woodpecker

A toy bird slides down a rod giving up energy to friction and pecking. A "loose clamp" on the ring stand demo is also shown.


1M40. Conservation of Energy


Demonstration Name



[:Nose Basher]

A bowling ball pendulum is held against the nose and allowed to swing out and back.


Cut a Pendulum String

Suspend a heavy bob on a thin string. As the ball reaches the lowest point of its swing the string is cut by a fixed razor blade. A kinematic analysis of the bob's flight gives the velocity it had when it left the pendulum. KE at that point should be equal to PE at the point it was released.


Galileo's Pendulum / Stopped Pendulum

Intercept the string of a pendulum by a post at the bottom of the swing. The bob will still return to its initial height.


[:Loop the Loop]

A ball is placed at various initial heights and allowed to roll down an incline and around a loop, assuming the ball has enough energy.


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. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000029000001000048000001&idtype=cvips&doi=10.1119/1.1937670&prog=normal AJP 29(1), 48].


Energy Well Track

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


[:Ball on "V" Tracks]

A ball is left to roll on a symmetrical and an unsymmetrical V-shaped track.


Ball in Curved Tracks

Balls are rolled down a series of curved tracks of the same height but different radii.


Roller Coaster

A ball rolls down a track with four horizontal sections of differing heights. The velocity is measured at each section. Optoelectronic detectors measure the speed of a ball at specific points on a roller coaster track. Could be adapted for lecture demonstration. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000059000003000283000001&idtype=cvips&doi=10.1119/1.16582&prog=normal AJP 59(3), 283].


[:Ballistic Pendulum]

The standard table top ballistic pendulum setup.


Ballistic Pendulum

The commercial swinging arm ballistic pendulum.


Ballistic Pendulum/Arrow

Fire a arrow from a bow into a hanging block of clay, measure the swing of the clay. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000036000006000558000001&idtype=cvips&doi=10.1119/1.1974981&prog=normal AJP 36(6), 558].


[:YoYo:Maxwell's Yo-Yo]

A large disc is suspended from a small axle so the string unwinds on the way down and rewinds on the way up showing that rotational energy is conserved.


Swinging Arm

A ball is dropped into a pivoting capturing arm from the height required to make it just complete one revolution.


Spinner and Pendulum

A ball suspended as a bifilar pendulum hits a ball of equal mass free to rotate in a horizontal circle.


Wilberforce Pendulum

A complicated apparatus converts elastic potential energy (spring) into rotational potential energy and back.


Height of a Ball

Rotate a 15.3in 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. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000029000010000709000002&idtype=cvips&doi=10.1119/1.1937563&prog=normal AJP 29(10), 709].


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.


Spring Energy Dependence (x squared)

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


Spring Gun

A spring gun shoots a small ball to different heights depending on the stored energy of the spring.


Mechanical Jumping Bean

A mailing tube jumps when a hidden mass moves upward under rubber band power. See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=PHTEAH000001000003000108000001&idtype=cvips&doi=10.1119/1.2350608&prog=normal TPT 1(3), 108].


Muzzle Velocity and Spring Constant

A method of using the potential energy of the cocked spring to calculate the muzzle velocity. (15% of the energy is lost.) See [http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=AJPIAS000053000011001114000002&idtype=cvips&doi=10.1119/1.14053&prog=normal AJP 53(11), 1114].


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.


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.


Tension in Wire when a Mass wings

A spring scale is suspended between two masses. Set one swinging and note the change in the spring scale.


Celts or Rattle-Back

A Toy that demonstrate energy conservation with rotational motion.


Drop Poppers

High Bounce Paradox: Drop inside out halved racket ball on to the floor or tabletop. It bounces back higher than the height from which it was dropped.


1M50. Mechanical Power


Demonstration Name



Prony Brake

A belt fastened to two spring scales is strung under tension around a large pulley which is mounted to a frame.


Power Bicycle

Attach a 2" diameter axle to the rear of a bike and use it to lift a weight via a pulley on the ceiling. See [http://physicslearning.colorado.edu/PIRA/Sutton/PARTI.pdf#pagemode=none&page=1 Sutton M-136].


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.




fw: WorkEnergy (last edited 2018-07-18 17:06:07 by srnarf)