A voltmeter has a range 0-V with a series res | vedclass

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(D) For a galvanometer with resistance $G$ to be converted into a voltmeter,a resistance $R$ is connected in series. The full-scale deflection current

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$V' < 2V$

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(D) For a galvanometer with resistance $G$ to be converted into a voltmeter,a resistance $R$ is connected in series. The full-scale deflection current $i_g$ remains constant.For the first case: $i_g = \frac{V}{R + G}$For the second case: $i_g = \frac{V'}{2R + G}$Equating the two expressions for $i_g$: $\frac{V}{R + G} = \frac{V'}{2R + G}$Rearranging for $V'$: $V' = V 	imes \frac{2R + G}{R + G}$$V' = V 	imes \frac{2(R + G) - G}{R + G} = V 	imes \left( 2 - \frac{G}{R + G} ight)$$V' = 2V - \frac{VG}{R + G}$Since $\frac{VG}{R + G} > 0$,it follows that $V' < 2V$.

$A$ voltmeter has a range $0-V$ with a series resistance $R$. With a series resistance $2R$,the range is $0-V'$. The correct relation between $V$ and $V'$ is

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