Two circular coils A and B are placed close to each other. If the current in the coil A is changed, will some current be induced in the coil B? Give reason.

Answer

N/a

Explanation

If the current in coil A is 'switched on' or 'switched off', then an electric current is induced in the coil B (see Figure given here). This can be explained as follows :
(i) When we switch on current in coil A, it becomes an electromagnet and produces a magnetic field around coil B. The effect is just the same as pushing a magnet into coil B. So, an induced current flows in coil B for a moment. When the current in coil A becomes steady, its magnetic field also becomes steady and the current in coil B stops.
(ii) When we switch off the current in coil A, then its magnetic field in coil B stops quickly. This effect is just the same as pulling a magnet quickly out of coil B. So, in this case an induced current flows in coil B in the opposite direction.