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Manipal MET2014PhysicsRotational Motion

A solid sphere of mass M , radius R and having moment of inertia about an axis passing through the centre of mass as I , is recast into a disc of thickness t , whose moment of inertia about an axis passing through its edge and perpendicular to its plane remains I . Then, radius of the disc will be

Options

  1. A2 R 15
  2. BR 2 15
  3. C4 R 15
  4. DR 4

Correct answer

A. 2 R 15

Step-by-step solution

aligned 2 5 M R^2 & = 3 2 M r^2 r & = 2 R 15 aligned

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