Lenz's Law, Eddy Currents & Induced Electric Field
A copper ring is held horizontally and a bar magnet is dropped through the ring with its length along the axis of the ring. The acceleration of the falling magnet while it is passing through the ring is
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Answer: (b)
- The magnet's flux through the closed ring changes as it falls, inducing a current.
- By Lenz's law the induced current opposes the motion (repels while approaching, attracts while leaving).
- So the magnet's acceleration is less than , answer (b).