Q 12-03-015NEETNEET 2021Top questionEasy
In a potentiometer circuit a cell of EMF $1.5$ V gives balance point at $36$ cm length of wire. If another cell of EMF $2.5$ V replaces the first cell, then at what length of the wire, the balance point occurs ?
Answer: (B) $60$ cm
The balancing length is proportional to the emf: $E \propto l$.
$$l_2 = 36 \times \frac{2.5}{1.5} = 60\ \text{cm}$$
Solution by Sreeraj P, M.Sc Physics