8B40.50 - Magnetic Field Coupling
Place the tennis ball on the bench and spin it observing that the ball spins for a long period of time. Place the dish with the Lycopodium powder and water on an overhead projector. Then position the ball above the dish with water and Lycopodium powder and spin it and allow it to drop into the dish. Notice that the ball drags a layer of water around with it and slows down fairly quickly.
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