Q. The deflection in moving coil galvanometer is reduced to half, when it is shunted with a 40 $\Omega$ coil. The resistance of the galvanometer is
A) 60 $\Omega$
B) 10 $\Omega$
C) 40 $\Omega$
D) 20 $\Omega$
Explanation
(c) Here, $i_{g} = \frac{1}{2}i;\ \ \ \ S = 40\Omega,$ G=?
$G = \left( i - i_{g} \right)S/i_{g}$ = $\frac{(i - i/2) \times 40}{i\ \text{/}2}$ =$40\Omega$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.