Q 12-04-111JEE MainJEE Main 2023 (31 Jan, Shift 2)Medium
The number of turns of the coil of a moving coil galvanometer is increased in order to increase current sensitivity by $50\%$. The percentage change in voltage sensitivity of the galvanometer will be
Answer: (D) $0\%$
Current sensitivity $\dfrac{NAB}{k}\propto N$, so $N$ rises by $50\%$. The resistance of the coil is proportional to the length of wire, so it also rises by $50\%$.
Voltage sensitivity $=\dfrac{\text{current sensitivity}}{R}$ is unchanged: $0\%$.
Solution by Sreeraj P, M.Sc Physics