Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
हिन्दीAn engine needs to transmit a torque of \( 180 \text{ N m} \) to maintain a rotor at a uniform angular speed of \( 200 \text{ rad s}^{-1} \). If the engine operates with an efficiency of \( 75\% \), the power input supplied to the engine is:
Correct answer · Option 1
\( 48 \text{ kW} \)
Explanation
Output power \( P_{\text{out}} = \tau \omega = 180 \times 200 = 36000 \text{ W} = 36 \text{ kW} \). Efficiency \( \eta = 0.75 \implies P_{\text{in}} = \frac{P_{\text{out}}}{\eta} = \frac{36}{0.75} = 48 \text{ kW} \).