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 ................. $\Omega$
JEE MAIN 2019, Medium
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$\frac{{30R}}{{R + 30}} = 30 \times 00.95$
$ \Rightarrow \,R = 570\,\Omega $
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