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JEE Main20207 Jan 2020Morning ShiftPhysicsRotational MotionActual

The radius of gyration of a uniform rod of length l , about an axis passing through a point l 4 away from the centre of the rod, and perpendicular to it, is:

Options

  1. A1 4 l
  2. B1 8 l
  3. C7 48 l
  4. D3 8 l

Correct answer

C. 7 48 l

Step-by-step solution

M l 2 12 + M l 4 2 = M K 2 l 2 12 + l 2 16 = K 2 K = 7 48 l

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