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JEE Main202118 Mar 2021Evening ShiftPhysicsRotational MotionActual

Consider a uniform wire of mass M and length L . It is bent into a semicircle. Its moment of inertia about a line perpendicular to the plane of the wire passing through the centre is :

Options

  1. A1 4 M L 2 π 2
  2. B2 5 M L 2 π 2
  3. CM L 2 π 2
  4. D1 2 M L 2 π 2

Correct answer

C. M L 2 π 2

Step-by-step solution

π r = L ⇒ r = L π I = M r 2 = M L 2 π 2

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