Question

A metal ring kept (supported by a card borad) on the top of a fixed soleniod carry a current I as shown in figure. The center of the ring coincides with the axis of the solenoid. If the current in the soleniod is switched off, then

Answer 1

Correct Answer - b
When the current in the solenoid swith off, magnetic flux linked with the solenoidl and hence with metal ring decreases. Current induced in the metal ring is clockwise, i.e., in the same direction as the solenoid current. So, they will attract each other. therefore, the metal ring will remain onthe carboard.