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MHT CET202014 Oct 2020Morning ShiftPhysicsRotational MotionActual

Let M and L be the mass and length of thin uniform rod respectively. In 1^ st case, axis of rotation is passing through centre and perpendicular to its length. In 2^ nd case, axis of rotation is passing through one end and perpendicular to its length. The ratio of radius of gyration in first case to second case is

Options

  1. A3: 1
  2. B1: 2
  3. C2: 1
  4. D1: 3

Correct answer

B. 1: 2

Step-by-step solution

array l I ₁= ML ² 12 = MK ₁² I ₂= ML ² 3 = MK ₂² k ₂= L 3 k ₁ k ₂ = 1 2 array K ₁= L 12 = L 2 3

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