Class 11PhysicsSystem of Particles and Rotational MotionEnergy conservation, Kinetic Energy, Work and Power of Rotational Motion
EasyTo maintain a rotor at a uniform angular speed of $200 \; rad \; s^{-1}$,an engine needs to transmit a torque of $180 \; N \; m$. What is the power required by the engine (in $; kW$)? (Note: uniform angular velocity in the absence of friction implies zero torque. In practice,applied torque is needed to counter frictional torque). Assume that the engine is $100 \%$ efficient.
- A$36$
- B$18$
- C$72$
- D$9$
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