5K40.45 - Motor - Generator Pairs

Code Number:
Demo Title:
Motor - Generator Pairs
Motors as Generators, Generators as Motors
Area of Study:
Electricity & Magnetism
2 Genecon Generators.

Video Credit: Jonathan M. Sullivan-Wood

Hook the two generators together.  If you turn one generator the other Genecon acts as a motor.  Reversing the positions of the Genecons will have the same effect.  This shows that a motor and a generator are the same thing, it just depends on whether you are putting electricity into or taking electricity out of the system.

The car has a motor that can also be used as a generator.  Run the car with the batteries in place and notice how the lights work.  Take the batteries out and run the car across the lecture bench.  The lights will still light up.

  • D. S. Goodman, J. E. Wells, "Energy Conservation in a Motor-Driven Generator", TPT, Vol. 59, #3, March 2021, p. 210.
  • Christopher Chiaverina, "The Versatile Constant Velocity Car", TPT, Vol. 58, #7, Oct. 2020, p. 524.
  • Carl E. Mungan, "Motor Demonstration Using a Hand-Cranked Genecon", TPT, Vol. 52, #7, Oct. 2014, p. 422.
  • Robert Beck Clark, "The Simplest Generator from the Simplest Motor?", TPT, Vol. 44, #2, Feb. 2006, p. 121.
  • Christopher Chiaverina, "The Simplest Motor?", TPT, Vol. 42, #9, Dec. 2004, p. 553.
  • John A. Johnson, Franklin Miller Jr., and Thomas B. Greenslade Jr., "A Motor is a Generator and Vice Versa", TPT, Vol. 40, #3, Mar. 2002, p. 185.
  • Gordon R. Gore, "A Colorful Current Event", TPT, Vol. 32, #6, Sept. 1994, p. 375.
  • Don D. Duncan, "A Generator-Motor Model", TPT, Vol. 16, #2, Feb. 1978, p. 94.
  • John A. Johnson and Franklin Miller Jr., "A Motor is a Generator and Vice Versa", TPT, Vol. 14, #1, Jan. 1976, p. 36.
  • Martin C. Sagendorf, "Hand-Cranked Generator & Motor", Physics Demonstration Apparatus, 2009, p. 70.
  • Cy Tymoney, "Sneaky Electrical Generator", Sneakiest Uses for Everyday Things, p. 114.
  • Robert Ehrlich, "N.6. Motor Driver and Slave", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 169.
  • Curt Suplee, "Around and Around", Everyday Science Explained, National Geographic, p. 94 - 95.

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