To maintain a rotor at a uniform angular speed of $100\, rad\, s^{-1}$, an engine needs to transmit torque of $100\, Nm$. The power of the engine is

  • A

    $10\,kW$

  • B

    $100\,kW$

  • C

    $10\,mW$

  • D

    $100\,mW$

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