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MHT CET202521 Apr 2025Evening 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 its own axis is

Options

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

Correct answer

B. y^2 2 x

Step-by-step solution

Rotational kinetic energy and angular momentum are defined by the equations K = 1 2 I ^2 and L = I , respectively. Solving the angular momentum equation for yields = L I . Substituting this into the energy equation gives K = 1 2 I ( L I )^2 = 1 2 L^2 I . Rearranging for moment of inertia results in I = L^2 2K . Using the given values K = x and L = y produces I = y^2 2x , which corresponds to option B.

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