Question

Sensitivity of moving coil galvanometer is 'S'. If shunt of `1/8` th of the resistance of galvanometer is connected to moving coil galvanometer, its sensitivity becomes ______.

विकल्प

• `"S"/3`

• `"S"/6`

• `"S"/9`

• `"S"/12`

Answer 1

Sensitivity of moving coil galvanometer is 'S'. If shunt of `1/8` th of the resistance of galvanometer is connected to moving coil galvanometer, its sensitivity becomes `underlinebb("S"/9)`.

Explanation:

S = `"G"/8` (Given)                    ...(i)

And, S = `"G"/("n"-1)`               ...(ii)

From eqs. (i) and (ii),

`"G"/8="G"/("n"-1)` ⇒ 8 = n - 1

∴ n = 8 + 1 = 9

Since, the range of galvanometer is increased by 9 times, therefore its sensitivity  reduces to `"S"/9`