13A10.10 - Perpetual Motion Machines - Relaxation Oscillators

Code Number:
Demo Title:
Perpetual Motion Machines - Relaxation Oscillators
Area of Study:
Perpetual Motion

Video Credit: Jonathan M. Sullivan-Wood.

Two versions of this are available.  Use a power supply to power the lights which will produce enough heat to drive the pulse glass. 

Pour liquid nitrogen into the cups and place them in at the top of the stand to drive the pulse glass.  

We have a variety of relaxation oscillators available.  Look at these webpages:

3A95.10 - Relaxation Oscillators

6-00.00 - Stroboscope (we have small variable frequency strobe lights available).

2B60.30 - Tantalus Cups

3D32.15 - Stadium Horn

4C30.25 - Geyser

4C31.30 - Drinking Bird

4C31.37 - Franklin's Pulse Glass Engine

5A40.70 - Kelvin Water Dropper

5F30.60 - Relaxation Oscillators - Neon Bulb, Doorbell, and Strobe Lights

10A06.10 - Relaxation Oscillators

13A10.10 - Perpetual Motion

  • K. P. Trout and Charles A. Gaston, "An Unexpected Heat Engine", TPT, Vol. 50, #1, Jan. 2012, p. 32.
  • Paul Chagnon, "Animated Displays V: Relaxation Oscillators", TPT, Vol. 32, # 7, p. 432- 436, Oct. 1994.
  • H. Richard Crane, "Three Intuition Teasers", TPT, Vol. 29, #3, Mar. 1991, p. 593. 
  • Donna A. Berry, "A 'Perpetual Motion' Toy?", TPT, Vol. 20, #5, May 1982, p. 319, also A Potpourri of Physics Teaching Ideas - Toys, p. 267.
  • Maurice Bruce Stewart, "The Marquess of Worcester's Perpetual Motion Machine", TPT, Vol. 19, #1, Jan. 1981, p. 37.
  • Albert A. Bartlett and Joseph Dreitlein, "A Possible Solution to the Energy Crisis - Part I - The Archimedes Wheel", TPT, Vol. 13, #2, Feb. 1975, p. 108.
  • Albert A. Bartlett, Joseph Dreitlein, "A Possible Solution to the Energy Crisis - Part II - The Capillary Pump", TPT, Vol. 13, #3, Mar. 1975, p. 175.
  • Problems, "A Perpetual Motion Device - A Solution", TPT, Vol. 5, #2, Feb. 1967, p. 88.
  • Herbert H. Gottlieb, Little Stinkers, "A Perpetual Motion Device",  TPT, Vol. 4, #1, Jan. 1966, p. 46.
  • Little Stinkers, "Perpetual Motion Machine", TPT, Vol. 3, #5, May 1965, p. 233.
  • Little Stinkers, "Another Perpetual Motion Device", TPT, Vol. 3, #4, Apr. 1965, p. 186.
  • Little Stinkers, "Perpetual Motion Machines", TPT, Vol. 3, #3, Mar. 1965, p. 138.
  • Little Stinkers, "Violation of the First Law of Thermodynamics", TPT, Vol. 2, #8, Nov. 1964, p. 383.
  • George H. Brigman, "The Martini Perpetual Motion Machine: A Semiprogrammed Problem", AJP, Vol. 40, #7, July 1972, p. 1001.
  • Lindsey Kratochwill, "The Greatest Cover Ever Made... Again", Popular Science, May 2014, p. 94.
  • James M. Robitaille, "Quantum Energy Generator", March 2014, (Not possible under current physics conditions).
  • Vicki Cobb and Kathy Darling, "Burning a Candle at Both Ends", Bet You Can!, p. 92.
  • Martin Gardner, "Perpetual Motion", Smart Science Tricks, p. 74.
  • Martin Gardner, "Gravity Machine", Entertaining Science Experiments With Everyday Objects, p. 82.
  • Martin Gardner, "Candle Seesaw", Science Tricks, p. 23.
  • Robert Ehrlich, "8.18 - Burning the Candle at Both Ends", Why Toast Lands Jelly-Side Down, p. 142.
  • Tik L. Liem, "The Burning Candle Seesaw", Invitations to Science Inquiry - Supplement to 1st and 2nd Ed. p. 98.
  • Simon Quellen Field, "A Bimetal Strip Heat Engine", Gonzo Gizmos, p. 156.

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