Question

When a bar magnet is pushed towards ( or away ) from the coil connected to a galvanometer, the pointer in the galvanometer deflects. Identify the phenomenon causing this deflection and write the factors on which the amount and direction of the deflected depends. State the laws describing this phenomenon.

Answer 1

The phenomenon involved is electromagnetic induction (EMI). For the deflection amount depends upon the speed of movement of the magnet or rate of change of flux. Direction depends on the sense ( towards or away) of the movement of the magnet
Direction of deflection is according to Lenz's law.
The law describing the phenomenon is:
The magnitude of the induced emf in a circuit is equal to the rate of change of the magnetic flux through the circuit.
$$\varepsilon =-\dfrac{d\varphi_B}{dt}$$