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To maintain a rotor at a uniform angular...

To 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 ? (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.

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Here `a=200" rads"^(-1)`, Torque `tau=180Nm`
Power P = torque `(tau)xx` angular speed `(omega)`
`=180xx200=36000` Watt = 36 kW
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