JEE Mains · Physics · STD 12 - Current electricity
- JEE Mains 2025
- Medium
- MCQ
A motor operating on 100 V draws a current of 1 A. If the efficiency of the motor is \(91.6 \%\), then the loss of power in units of \(\mathrm{cal} / \mathrm{s}\) is _________.
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(2\)
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & P_{\text {input }}=V i=100 \mathrm{~W} \\ & \eta=\frac{P_{\text {out }}}{P_{\text {input }}}=0.916\end{aligned}\)
\(\begin{aligned} & P_{\text {out }}=91.6 \mathrm{~W} \\ & \text { Loss }=100-91.6=8.4 \mathrm{~J} / \mathrm{s}=2 \mathrm{cal} / \mathrm{s}\end{aligned}\)
\(\begin{aligned} & P_{\text {out }}=91.6 \mathrm{~W} \\ & \text { Loss }=100-91.6=8.4 \mathrm{~J} / \mathrm{s}=2 \mathrm{cal} / \mathrm{s}\end{aligned}\)
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