A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is (i) pushed into the coil, (ii) withdrawn from inside the coil, (ii) held stationary inside the coil?

Explanation

(i) When a bar magnet is pushed into the coil of insulated copper wire connected to a galvanometer, an induced current is set up in the coil. As a result, galvanometer gives a deflection (say towards left).
(ii) When the bar magnet is withdrawn from inside the coil, again an induced current is set up in the coil. However, now direction of induced current is opposite to that in earlier case. Hence, deflection in galvanometer is in reverse direction (say towards right).
(iii) If the bar magnet is held stationary inside the coil, then there is no induced current in the coil. As a result, galvanometer does not show any deflection.