Two circular coils P and Q are kept close to each other, of which coil P carries a current. What will you observe in the galvanometer connected across the coil Q (a) if current in the coil P is changed?(b) if both the coils are moved in the same direction with the same speed?Give reason to justify your answer in each case.

(a) If current in the coil P is changed, then we observe that the galvanometer shows deflection because when the current in P is changed, the magnetic field lines associated with coil Q will vary causing an induced current in Q.

(b) If both the coils are moved in the same direction with the same speed, we observe no deflection in the galvanometer because there will not be any change in magnetic field lines associated with coil Q, so no induced current.