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MHT CET202122 Sep 2021Evening ShiftPhysicsRotational MotionActual

Two rings of radius ' R ' and ' n R ' made of same material have the ratio of moment of inertia about an axis passing through its centre and perpendicular to the plane is 1: 8 . The value of ' n ' is (mass per unit length = )

Options

  1. A2
  2. B4
  3. C1
  4. D3

Correct answer

A. 2

Step-by-step solution

aligned & I ₁= 1 2 MR ^2 & I ₂= 1 2 ( nM )( nR )^2= 1 2 n ^3 MR ^2 & I ₁ I ₂ = 1 n ^3 = 1 8 & n ^3=8 or n =2 aligned

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