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MHT CET202020 Oct 2020Evening ShiftPhysicsRotational MotionActual

If the spherical planet of mass ' M ^ and radius 'R' suddenly shrinks to half its size, its mass reduces to half. The new moment of inertia of the planet about its diameter is

Options

  1. AMR ² 10
  2. BMR ² 20
  3. C2 3 MR ²
  4. D2 5 MR ²

Correct answer

B. MR ² 20

Step-by-step solution

I ₁= 2 5 MR ² I ₂= 2 5 M 2 ( R 2 )²= 2 5 M 2 R² 4 = M R² 20

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