Consider four circuits shown in the figure be | vedclass

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(A) The power dissipated in a circuit is given by $P = \frac{E^2}{R_{eq}}$,where $E$ is the $EMF$ of the source and $R_{eq}$ is the equivalent resista

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(A) The power dissipated in a circuit is given by $P = \frac{E^2}{R_{eq}}$,where $E$ is the $EMF$ of the source and $R_{eq}$ is the equivalent resistance of the circuit.For $P$ to be maximum,$R_{eq}$ must be minimum.Let's calculate $R_{eq}$ for each circuit:$(a)$ Two resistors $R$ in parallel: $R_{eq} = \frac{R 	imes R}{R + R} = \frac{R}{2} = 0.5R$.$(b)$ Two resistors $R$ in series: $R_{eq} = R + R = 2R$.$(c)$ Two resistors $R$ in parallel,in series with $R$: $R_{eq} = \frac{R}{2} + R = 1.5R$.$(d)$ Two resistors $R$ in series,in parallel with $R$: $R_{eq} = \frac{(2R) 	imes R}{2R + R} = \frac{2R^2}{3R} = \frac{2}{3}R \approx 0.67R$.Comparing the values,$0.5R The minimum equivalent resistance is $0.5R$,which corresponds to circuit $(a)$.Therefore,the power dissipated is greatest in circuit $(a)$.

Consider four circuits shown in the figure below. In which circuit is the power dissipated the greatest? (Neglect the internal resistance of the power supply)

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