5H20.10 - Forces on Magnets - Torque

Code Number:
Demo Title:
Forces on Magnets - Torque
Torques on Magnets
Area of Study:
Electricity & Magnetism
Seal and Ball, Dancing Mary and Magic Mirror.

The magnets inside the toys are arranged in such a way that when the seal is brought close to the ball, the ball will begin to spin.

When the mirror is brought close to Dancing Mary she should also begin to rotate if placed on a smooth surface.

  • Raymond C. Turner,  "A Physics Toy: Magnetic Seal and Ball",  TPT, Vol. 25, # 9, p. 568, December 1987.
  • Donna A. Berry, "A "Perpetual Motion" Toy?", TPT, Vol. 20, # 5, May 1982, p. 319.
  • Jodi and Roy McCullough, "Magnetism with a Ballerina", The Role of Toys in Teaching Physics, p. 4.166.

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