Question

When a $12\Omega$ resistor is connected with a moving coil galvanometer, then its deflection reduces from 50 divisions to 10 divisions. The resistance of the galvanometer is

• A. $24\Omega$
• B. $36\Omega$
• C. $48\Omega$
• D. $60\Omega$

Answer 1

The correct option is C $48\Omega$


Here. current $\propto$deflection
So, $(i-i_g)R_s=\left(i_g\right)R_s(50k-10k)\times 12=10k\times R_g$
$40\times 12=10\times R_g{R}_g=48\Omega$