Question

The diagram given below shows two coils X and Y. The coil X is connected to a battery S and a key K. The coil Y is connected to a galvanometer G.

When the key K is closed state the polarity. 

i) At the end B of the coil X. 

ii) At the end C of the coil Y. 

iii) At the end C of the coil Y if the coil Y is (a) moved towards the coil X, (b) moved away from the coil X.

Answer 1

i) On closing the key K, the current at the end B of the coil X is anti-clockwise, therefore at this end there is a north pole. 

ii) While closing the key, polarity at the end C of the coil Y will be north. But there will be no polarity at the end C of the coil Y when the current becomes steady in the coil X 

iii) a) With the key K closed, while the coil Y is moved towards the coil X, the polarity at the end C of the coil Y is north. 

b) With the key K closed, while the coil Y is moved away from the coil X, the polarity at the end C of the coil Y is south.