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(C) The power rating of a bulb is given by the formula $P = \frac{V^2}{R}$,where $P$ is power,$V$ is voltage,and $R$ is resistance.For the bulb used i

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$\frac{R}{4}$

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(C) The power rating of a bulb is given by the formula $P = \frac{V^2}{R}$,where $P$ is power,$V$ is voltage,and $R$ is resistance.For the bulb used in India: $P = \frac{V_{India}^2}{R} = \frac{220^2}{R} = 60\,W$.For the bulb used in the $USA$: $P = \frac{V_{USA}^2}{R'} = \frac{110^2}{R'} = 60\,W$.Since the power $P$ is the same $(60\,W)$ in both cases,we can equate the expressions:$\frac{220^2}{R} = \frac{110^2}{R'}$$R' = R 	imes \left(\frac{110}{220}ight)^2$$R' = R 	imes \left(\frac{1}{2}ight)^2 = \frac{R}{4}$.

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

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