Question

Two circular coils A and B of insulated wires are kept close to each other. Coil A is connected to a galvanometer while coil B is connected to a battery through a key. What will you observe in coil A, if (a) current is passed through coil B by plugging the key, (b) the current is stopped by removing the plug from the key? (c) both the coils are moved in the same direction with the same speed? Explain your answer mentioning the name of the phenomena involved.

Answer 1

(a)As the key is closed, the galvanometer needle will deflect for a moment and then return to zero.
(b)As the key is removed ,again a momentary deflection (but more) because of the change in magnetic flux linked with the coil is observed in the galvanometer in opposite direction .
(c)With the key closed ,if the coil A and B are moved with the same speed in the same direction ,there is no deflection in the galvanometer because there is no change in the magnetic flux linked with the coil a.
The phenomenon involved is Electromagnetic induction.

Answer 2

A)there will be a deflection shown in galvanometer.

B) there will be again at deflection in Galvanometer But in opposite side direction because of the change in magnetic flux.

C) there will be no deflection in galvanometer

The phenomenon involved is magnetic induction..