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JEE Main202131 Aug 2021Evening ShiftPhysicsRotational MotionActual

A system consists of two identical spheres each of mass 1 . 5 kg and radius 50 cm at the ends of a light rod. The distance between the centres of the two spheres is 5 m . What will be the moment of inertia of the system about an axis perpendicular to the rod passing through its midpoint?

Options

  1. A1 . 905 × 10 5   kg   m 2
  2. B18 . 75   kg   m 2
  3. C19 . 05   kg   m 2
  4. D1 . 875 × 10 5   kg   m 2

Correct answer

C. 19 . 05   kg   m 2

Step-by-step solution

I = 2 5 M R 2 + M x 2 × 2 = 2 5 × 1 . 5 × 0 . 5 2 + 1 . 5 × 2 . 5 2 × 2 = [ 0 . 15 + 9 . 375 ] × 2 = 19 . 05 kgm 2

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