Seal and Ball, Dancing Mary and Magic Mirror

Code Number: 5H20.10

Demo Title: Forces on Magnets - Torque

Condition: Excellent

Principle: Torques on Magnets

Area of Study: Electricity & Magnetism

Equipment:

Seal and Ball, Dancing Mary and Magic Mirror.

Procedure:

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.

References:

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.

5H20.10 - Forces on Magnets - Torques

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