When two resistances $R_{1}$ and $R_{2}$ are connected in series and parallel with $120\ V$ line power consumed will be $25\ W$ and $100\ W$ respectively. Then the ratio of power consumed by $R_{1}$ to that consumed by $R_{2}$ will be

Question

Dr. Abubacker · Accepted Answer

(a) $P = \frac{V^{2}}{R} \Rightarrow \frac{P_{P}}{P_{S}} = \frac{R_{S}}{R_{P}} = \frac{(R_{1} + R_{2})}{R_{1}R_{2}/(R_{1} + R_{2})} = \frac{\left( R_{1} + R_{2} \right)^{2}}{R_{1}R_{2}}$
$\Rightarrow \frac{100}{25} = \frac{\left( R_{1} + R_{2} \right)^{2}}{R_{1}R_{2}} \Rightarrow \frac{R_{1}}{R_{2}} = \frac{1}{1}$

Q. When two resistances $R_{1}$ and $R_{2}$ are connected in series and parallel with $120\ V$ line power consumed will be $25\ W$ and $100\ W$ respectively. Then the ratio of power consumed by $R_{1}$ to that consumed by $R_{2}$ will be

Explanation

Reviewed by Dr. Abubacker

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