Question.
Which of the following terms does not represent electrical power in a circuit ?
(1) $I^{2} R$
(2) $\mathrm{IR}^{2}$
(3) VI
(4) $\mathrm{V}^{2} / \mathrm{R}$
Which of the following terms does not represent electrical power in a circuit ?
(1) $I^{2} R$
(2) $\mathrm{IR}^{2}$
(3) VI
(4) $\mathrm{V}^{2} / \mathrm{R}$
solution:
Electrical power, $\mathrm{P}=\mathrm{VI}=(\mathrm{IR}) \mathrm{I}=\mathrm{I}^{2} \mathrm{R}$
$\mathrm{P}=\mathrm{V} \mathrm{I}=\mathrm{V}\left(\frac{\mathrm{V}}{\mathrm{R}}\right)=\frac{\mathrm{V}^{2}}{\mathrm{R}}$
Obviously, $\mathrm{IR}^{2}$ does not represent electrical power in a circuit.
Thus, (2) is the correct answer.
Electrical power, $\mathrm{P}=\mathrm{VI}=(\mathrm{IR}) \mathrm{I}=\mathrm{I}^{2} \mathrm{R}$
$\mathrm{P}=\mathrm{V} \mathrm{I}=\mathrm{V}\left(\frac{\mathrm{V}}{\mathrm{R}}\right)=\frac{\mathrm{V}^{2}}{\mathrm{R}}$
Obviously, $\mathrm{IR}^{2}$ does not represent electrical power in a circuit.
Thus, (2) is the correct answer.
Click here to get exam-ready with eSaral
For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.