Question

A rectangular coil of a moving coil galvanometer contains 50 turns each having area 12 cm2 . It is suspended in radial magnetic field 0.025 Wb/m² by a fibre of twist constant 15 x10^-10 Nm/degree. Calculate the sensitivity of the moving coil galvanometer.

Answer 1

Given:-

N = 50, A = 12 cm² = 12 x 10^-4 m²,

B = 0.025 Wb/m²,

C = 15 x 10^-10 Nm/degree

To find:- Sensitivity (S_i)

Formula: S_i = NAB/C

Calculation: From formula,

${\displaystyle S_i=\frac{50\times 12\times {10}^{-4}\times 0.025}{15\times {10}^{-10}}}$

${\displaystyle \therefore S_i={10}^6\text{div/A}}$

The sensitivity of a moving coil galvanometer is 10⁶ div/A.