Question

In the figure a bar magnet moving towards the right or left induces an e.m.f. in the coils (1) and (2). Find, giving reason, the direction of induced currents through resistors AB and CD. When the magnet is moving (a) towards the right and (b) towards the left.

Answer 1

(a) When the magnet is moving towards right. When the magnet is moving towards right, the N pole of the magnet is moving away from coil (1) and is approaching towards coil (2), hence it forms S-pole in coil (1) (due to clockwise current) and the current is from A to B Fig. and S pole is also formed in coil (2). (due to induced clockwise current) and the current is from D to C.

(b) When the magnet is moving towards left. Here N-pole is approaching towards coil (1) and S-pole is receding away from coil (2), So N-pole is formed both in coil (1) and (2) as shown in Fig.