Two equal resistances when connected in series to a battery, consume electric power of $60\,W.$ If these resistances are now connected in parallel combination to the same battery, the electric power consumed will be .............. $W$
JEE MAIN 2019, Medium
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Assuming constant voltage supply
$P=60=\frac{V^{2}}{R_{1}+R_{2}}$ .......$(1)$
$ \text { And } P^{\prime}=\frac{V^{2}}{R_{1}}+\frac{V^{2}}{R_{2}}=\frac{2 V^{2}}{R_{1}} =4 P=4 \times 60 $
$=240 \,\mathrm{W} $
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