A $220\, volt$, $1000\, W$ bulb is connected across a $110\, volt$ mains supply. The power consumed will be ............ $W$
AIEEE 2003, Medium
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$\frac{{{P_1}}}{{{P_2}}} = {\left( {\frac{{{V_1}}}{{{V_2}}}} \right)^2}$$ \Rightarrow \frac{{1000}}{{{P_2}}} = {\left( {\frac{{220}}{{110}}} \right)^2} = 4$$ \Rightarrow $ ${P_2} = 250\,W$
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