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MHT CET202611 April 2026Morning ShiftPhysicsRotational MotionActual

A flywheel rotating about a fixed axis has a kinetic energy of 500 joule, if its angular frequency is 5 Hz, then calculate the moment of inertia of the wheel about the axis of rotation. ( ^2=10 )

Options

  1. A0.6 kg m ^2
  2. B1 kg m ^2
  3. C0.75 kg m ^2
  4. D0.15 kg m ^2

Correct answer

B. 1 kg m ^2

Step-by-step solution

Given kinetic energy K = 500 J and angular frequency f = 5 Hz. Angular velocity = 2 f = 2 5 = 10 rad/s. The rotational kinetic energy is given by K = 1 2 I ^2 . Substituting the values: 500 = 1 2 I (10 )^2 500 = 1 2 I (100 ^2) Given ^2 = 10 : 500 = 1 2 I (100 10) 500 = 500 I I = 1 kg m ^2 Answer: 1 kg m ^2

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