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A galvanometer of resistance 5.0Ω has full-sca...

A galvanometer of resistance 5.0Ω has full-scale deflection for a current of 100mA. How would its range be extended to 1.0A? By placing a resistance of

A.

59Ω in parallel

B.

95Ω in series

C.

45Ω in parallel

D.

45Ω in series

E.

95Ω in parallel

Correct answer is A

Given Data:
Ig = 100ma = 0.1A
Rg=5
where Is = I - Ig → 1 - 0.1

Is = 0.9

IgRg = IsRs


0.1 * 5 = 0.9 * Rs
Rs = 0.150.9

Rs = 59