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MHT CET20225 Aug 2022Evening ShiftPhysicsRotational MotionActual

A body is rotating about its own axis. Its rotational kinetic energy is ' x ' and its angular momentum is ' y '. Hence its moment of inertia about the axis is

Options

  1. Ax^2 2 y
  2. By 2 x
  3. Cx 2 y
  4. Dy^2 2 x

Correct answer

D. y^2 2 x

Step-by-step solution

The kinetic energy of a rotating body is given by x= I ^2 2 and the angular momentum is given by y = I , where I is the moment of inertia, the angular velocity. Therefore, we can write, y ^2=2 I ( I ^2 2 )=2 Ix On re-writing, I= y^2 2 x

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