A bulb has specification of one kilowatt and $250\, volts$, the resistance of bulb is .................. $\Omega$
A$125$
B$62.5$
C$0.25$
D$625$
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B$62.5$
b (b) $R = \frac{{{V^2}}}{P} = \frac{{{{(250)}^2}}}{{{{10}^3}}} = 62.5\,\Omega $
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