Question

Why we use rheostat in Meter bridge?

Answer 1

A rheostat is used in the circuit to ensure that even when the bridge is completely out of balance, the arm containing the Galvanometer should not draw excess current which, in turn, could damage it. It also adjusts the sensitivity of galvanometer as the deflection in galvanometer coil depends on the resistance of the circuit (which is varied using the rheostat). .