In the given figure $-1$, resistance of shown voltmeter is variable. Variation of whose reading with respect to its resistance is shown in figure $-2$. The value of $R$ is ............... $\Omega$
A$2$
B$4$
C$8$
D$16$
Medium
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C$8$
c $\mathrm{R}_{\mathrm{v}} \rightarrow \infty, \mathrm{V}_{\mathrm{R}} \rightarrow 8 \mathrm{\,volt}$
$8=\left(\frac{10}{R+2}\right) R \Rightarrow R=8\, \Omega$
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