A metre bridge is in a balanced position with $\frac{P}{Q}=\frac{l_{1}}{l_{2}}$. If we now completel

Question

A metre bridge is in a balanced position with $\frac{P}{Q}=\frac{l_{1}}{l_{2}}$. If we now completely interchange the positions of the galvanometer and the cell, what will happen to the position of the null point?

Professor PC Thomas Classes · Answer

(c) : The metre bridge is essentially a Wheatstone bridge. A fundamental property of a Wheatstone bridge is that its balance condition is independent of the respective positions of the battery and the galvanometer. Therefore, interchanging them does not affect the balance condition ($\frac{P}{Q}=\frac{l_{1}}{l_{2}}$), and the null point will remain exactly at the same location.