Question: A bar magnet falls through a metal ring . Will its acceleration be equal to ‘ g ‘ ?
Ans. No , acceleration of magnet will not be equal to g . It will be less than ‘g ‘ . This is because as magnet falls amount of magnetic flux linked with the ring changes . An induced current is developed in the ring which opposes the downward motion of the magnet .After the magnet has crossed the metal ring , amount of magnetic flux linked with the ring goes on decreasing . An induced current is developed in the ring and opposes the fall of magnet . Therefore downward acceleration of magnet continues to be less than ‘ g ’ .