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JEE Main202126 Feb 2021Morning ShiftPhysicsRotational MotionActual

Four identical solid spheres each of mass m and radius a are placed with their centres on the four corners of a square of side b . The moment of inertia of the system about one side of square where the axis of rotation is parallel to the plane of the square is :

Options

  1. A8 5 m a 2 + m b 2
  2. B4 5 m a 2 + 2 m b 2
  3. C8 5 m a 2 + 2 m b 2
  4. D4 5 m a 2

Correct answer

C. 8 5 m a 2 + 2 m b 2

Step-by-step solution

I = 2 × 2 5 m a 2 + 2 × 2 5 m a 2 + m b 2 I = 8 5 m a 2 + 2 m b 2

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