A potentiometer circuit has been set up for finding the internal resistance of a given cell. The main battery used across the potentiometer wire, has an emf of 2.0 V and a negligible internal resistance. The potentiometer wire itself is 4m long, When the resistance R, connected across the given cell, has values of.
(i) infinity (ii) 9.5 Ω
The balancing lengths', on the potentiometer wire are found to be 3 m and 2.85 m, respectively.
The value of internal resistance of the cell is