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Question
A rectangular coil of a moving coil galvanometer contains 100 turns, each having area
15 cm2. It is suspended in the radial magnetic field 0.03 T. The twist constant of suspension
fibre is 15 x 10-10 N-m/degree. Calculate the sensitivity of the moving coil galvanometer.
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Solution
Given: `N = 100, A = 15 cm^2 = 15 xx 10^-4 m^2`,
`B = 0.03 (Wb)/m^2`,
`C = 15 xx 10^-10 "Nm"/"degree"`
To find: Sensitivity (Si)
Formulae: `S_i=(NAB)/c`
`S_i=(100xx15xx10^-4xx0.03)/(15xx10^-10)`
`S_i=3xx10^6 "div"/A`
The sensitivity of a moving coil galvanometer is `3 xx 10^6 "div"/A`.
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