In India electricity is supplied for domestic use at $220 \,V$. It is supplied at $110 \,V$ in USA. If the resistance of a $60 \,W$ bulb for use in India is $R$, the resistance of a $60 \,W$ bulb for use in USA will be
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(c)

$R=\frac{V^2}{P}$

$R=\frac{(220)^2}{60}$

$R^{\prime}=\frac{(110)^2}{60}$

$\frac{R}{R^{\prime}}=4 \Rightarrow R^{\prime}=\frac{R}{4}$

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