# Q. The actual value of resistance R, shown in the figure is $30 \Omega$. This is measured in an experiment as shown using the standard formula $R = \frac{V}{I}$ , where V and I are the readings of the voltmeter and ammeter, respectively. If the measured value of R is 5% less, then the internal resistance of the voltmeter is :

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Solution:

## $0.95 R = \frac{RR_{v}}{R+R_{v}}$ $0.95 \times30 = 0.05 R_{v}$ $R_{v} = 19 \times30 = 570 \Omega$

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