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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.
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Solution
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 (Si)
Formula: Si = NAB/C
Calculation: From formula,
`S_i=(50xx12xx10^-4xx0.025)/(15xx10^-10`
`thereforeS_i=10^6"div/A"`
The sensitivity of a moving coil galvanometer is 106 div/A.
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