A galvanometer having a resistance of 20Ω and 30 division on both sides has figure of merit 0.005 ampere/ division. The resistance that should be connected in series such that it can be used as a volt

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A galvanometer having a resistance of 20Ω and 30 division on both sides has figure of merit 0.005 ampere/ division. The resistance that should be connected in series such that it can be used as a voltmeter upto 15 volt, is:

TestHub · Accepted Answer

Deflection current = Ig m a x ​ = n x k = 0.005 × 30 Where, n = Number of divisions = 30 and k = 0.005 amp / division = 15 × 1 0 − 2 = 0.15 v = I g ​ [ 20 + R ] 15 = 0.15 [ 20 + R ] 100 = 20 + R R = 80Ω ​

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