If resistance of voltmeter is $10000 \,\Omega$ and resistance of ammeter is $2 \,\Omega$ then find $R$ when voltmeter reads $12\,V$ and ammeter reads $0.1\, A$ ............... $\Omega$
A$118 $
B$120$
C$124 $
D$114$
Medium
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A$118 $
a (a) According to following figure
Reading of voltmeter = Potential difference between $A$ and $B$ = $i (R + 2)$
$ \Rightarrow $ $12 = 0.1 (R + 2)$
$ \Rightarrow $ $R = 118\,\Omega$.
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