A metal 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 is

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(3) less than g. As the magnet falls, the flux through the ring changes, so a current is induced in it. By Lenz's law that current flows in the direction that opposes the change, which means the ring's field repels the approaching pole and attracts the receding one. Either way the magnetic force on the magnet is upward, opposing its fall. So the net downward force is less than the weight and the acceleration is less than g. Energy is conserved: the kinetic energy the magnet does not gain appears as heat in the ring.

A metal 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 is

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Why the other options are wrong