What is electromagnetic induction ? Explain.

Explanation

The phenomenon in which an emf and hence a current is induced in a closed circuit, due to a change in the magnetic flux linked with it ,is called electromagnetic induction.
Whenever there is a relative motion between the magnet and the coil, a momentary current is induced , resulting in a momentary deflection in the galvanometer. When the magnet moves towards the coil the magnetic flux linked with the coil increases, and when moved away from the coil, the flux decreases.