If power in $3\,\Omega $ is $27\,W$ then what is the power in $2\,\Omega $ ................. $W$
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in series $\mathrm{P} \propto \mathrm{R}$
$\frac{27}{P}=\frac{3}{4 / 3} \Rightarrow P=12 \mathrm{\,W}$
in parallel combination
$\mathrm{P}=\mathrm{P}_{1}+\mathrm{P}_{2}$ and $\mathrm{P} \propto \frac{1}{\mathrm{R}} \Rightarrow \frac{\mathrm{P}_{1}}{\mathrm{P}_{2}}=\frac{4}{2}$
$\Rightarrow \mathrm{P}_{2}=\frac{\mathrm{P}_{1}}{2} \Rightarrow \mathrm{P}=12=\mathrm{P}_{1}+\mathrm{P}_{2}$
$12=\frac{3 \mathrm{P}_{1}}{2} \Rightarrow \mathrm{P}_{1}=8 \mathrm{\,W}$
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