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 4 m long. When the resistance, R, connected acrose the given cell, has values of .
(i) infinity (ii) 9.5 Ω
The 'balancing lengths, on the potentiometer wire are found to be 3m and 2.85 m, respectively. The value of internal resistance of the cell is :
(A) 0.25 Ω
(B) 0.95 Ω
(C) 0.5 Ω
(D) 0.75 Ω
