Q. To sand 10% of main current through a moving coil galvanometer of resistance 9$\ \Omega$ shut required
A) 9$\ \Omega$
B) 11$\ \Omega$
C) 10$\ \Omega$
D) 9.9$\ \Omega$
Explanation
(b) Let $R = 100\Omega\ $
$\therefore\ \ \ R^{'}\mathbf{=}100 + 100 \times \frac{10}{100}$
$\ \ \ \ \ \ \ \ \ \ \ \ = 110\Omega\ $
$\therefore\ \mathrm{\Delta}R = R^{'} - R$
$\ \ \ \ \ \ \ \ \ \ \ \ = 110 - 99 = 11\Omega$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.