Q. The deflection in a galvanometer falls from 50 division to 20 when a 12 $\Omega$ shunt is applied. The galvanometer resistance is
A) 18 $\Omega$
B) 36 $\Omega$
C) 24 $\Omega$
D) 30 $\Omega$
Explanation
(a) $i = 50\ k;\ i_{g} = 20k,$ where $k$ is the figure of metit of galvanometer; $S = i_{g}G/(i - i_{g})$;
So, $12 = \ \frac{20k.G}{(50k - 20k)}$
On solving we get $G = 18\Omega$.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.