5K20.57 - Rotating Copper & Aluminum Disks

Code Number:
Demo Title:
Rotating Copper & Aluminum Disks
Magnetic Induction
Area of Study:
Electricity & Magnetism
Horseshoe magnet, suspended rings, turntable or lazy susan.

Place the magnet on the turntable and then suspend the ring between the poles of the magnet.  The ring will follow the magnet as if locked in position due to magnetic induction.

  • P. W. Matthews, "Simple Classroom Demonstration of Lenz's Law and the AC Induction Motor", AJP, Vol. 33, #  12, p. 1082.

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