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MHT CET202617 April 2026Morning ShiftPhysicsRotational MotionActual

Two bodies A and B have moment of inertia I_A and I_B , and angular momenta L_A and L_B respectively. Both of them have same kinetic energy of rotation. So the ratio L_A to L_B is

Options

  1. AI_A I_B
  2. BI_A^2 I_B^2
  3. CI_A I_B
  4. DI_B I_A

Correct answer

C. I_A I_B

Step-by-step solution

The rotational kinetic energy of a body is given by K = L^2 2I , where L is the angular momentum and I is the moment of inertia. Given that both bodies have the same rotational kinetic energy, K_A = K_B . L_A^2 2I_A = L_B^2 2I_B L_A^2 L_B^2 = I_A I_B Taking the square root on both sides, we get: L_A L_B = I_A I_B Answer: I_A I_B

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