How can we convert a galvanometer into a volt | vedclass

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(A) galvanometer is a sensitive device that can measure small currents. To convert it into a voltmeter,which measures potential difference,we need to

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By connecting a high resistance in series with the galvanometer.

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(A) galvanometer is a sensitive device that can measure small currents. To convert it into a voltmeter,which measures potential difference,we need to increase its resistance significantly so that it draws negligible current from the circuit.This is achieved by connecting a high resistance,known as a series resistor $(R_s)$,in series with the galvanometer coil.Let $G$ be the resistance of the galvanometer and $I_g$ be the current for full-scale deflection. If we want to measure a voltage $V$,the total resistance of the voltmeter will be $R_{total} = G + R_s$.According to Ohm's law,$V = I_g(G + R_s)$.Rearranging for $R_s$,we get $R_s = (V / I_g) - G$.

How can we convert a galvanometer into a voltmeter?

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