Q 12-04-088JEE MainJEE Main 2024 (29 Jan, Shift 1)Medium
The deflection in a moving coil galvanometer falls from 25 divisions to 5 divisions when a shunt of $24\ \Omega$ is applied. The resistance of the galvanometer coil will be:
Answer: (B) $96\ \Omega$
Deflection is proportional to the current through the coil. With the shunt, the fraction of current through the coil is
$$\frac{I_g}{I} = \frac{S}{S + G} = \frac{5}{25} \;\Rightarrow\; \frac{24}{24 + G} = \frac15 \;\Rightarrow\; G = 96\ \Omega$$
Solution by Sreeraj P, M.Sc Physics