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MHT CET202012 Oct 2020Morning ShiftPhysicsRotational MotionActual

A wheel is at rest in horizontal position. Its M.I. about vertical axis passing through its centre is 'I'. A constant torque ' ^ 'acts on it for ' t ' second. The change in rotational kinetic energy is

Options

  1. A² t² 2 I
  2. B[ t 2 I ]
  3. C[ t 2 I ]^ 1 2
  4. D[ t 2 I ]²

Correct answer

A. ² t² 2 I

Step-by-step solution

If is the angular acceleration, then the angular velocity after time t is given by = t but = I = I t kinetic energy K = 1 2 I ²= 1 2 I ² I ² t ²= ² t ² 2 I

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