Null point in the galvanometer is obtained when a cell  of emf E and internal resisance r is
Channel: Doubtnut
Date: 2021-11-02

Null point in the galvanometer is obtained when a cell  of emf E and internal resisance r is connncted across the length of 22 cm wire of  the potentiometer . Now a resistane of `10Omega` is connected across the terminals of the cell (by closing the key K) and null point is obtained against the length of cm. The internal resistance r of the cell is -