Question

A small valued resistance XY is connected across the ends of a coil. Predict the direction of induced current in the resistance XY when.

(i) South pole of a magnet moves towards end A of the coil. 

(ii) South pole of a magnet moves away from end A of the coil.

Answer 1

(i) According to the Lenz’s Law induced emf will oppose the source of the charge, thus to oppose the approaching South Pole magnetic South Pole will be developed at the end of the magnet. Thus the current will flow in the clockwise direction as shown in the figure below.

(ii) According to the Lenz’s Law induced emf will oppose the source of the charge, thus to oppose the going away South Pole magnetic North Pole will be developed at the end of the magnet so that the south pole of the magnet do not go away. Thus the current will flow in the anticlockwise direction as shown in the figure below.