Current sensitivity of a moving coil galvanometer is (5 ,div... | Physics | SolveeIt | Solveeit

Today, August 18

Question

Current sensitivity of a moving coil galvanometer is $5 \,div/mA$ and its voltage sensitivity (angular deflection per unit voltage applied) is $20 \,div/V$ . The resistance of the galvanometer is

A

$500 \, \Omega$

B

$40 \, \Omega$

C

$250 \, \Omega$

D

$25 \, \Omega$

Answer

$250 \, \Omega$

Explanation

Solution

Current sensitivity
$I_S = \frac{NBA}{C}$
Voltage sensitivity
$V_S = \frac{NBA}{CR_G}$
So, resistance of galvanometer
$R_G = \frac{I_S}{V_S} = \frac{5 \times 1}{20 \times 10^{-3}} = \frac{5000}{20} = 250 \, \Omega$