3.12 In a potentiometer arrangement, a cell of emf 1.25 V gives a balance point at 35.0 cm length of the wire. If the cell is replaced by another cell and the balance point shifts to 63.0 cm, what is the emf of the second cell?
= 1.25 V , = 35 cm
And, = 63 cm
Let be the voltage in the second case.
Now, the balance condition is given by :
Therefore, the emf of the second cell = 2.25 V