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JEE Main20252 Apr 2025Morning ShiftPhysicsRotational MotionActual

Moment of inertia of a rod of mass ' M ' and length 'L' about an axis passing through its center and normal to its length is ' '. Now the rod is cut into two equal parts and these parts are joined symmetrically to form a cross shape. Moment of inertia of cross about an axis passing through its center and normal to plane containing cross is :

Options

  1. A/ 4
  2. B/ 8
  3. C/ 2

Correct answer

B. / 8

Step-by-step solution

= M ^2 12 aligned & ^ =2 [ M 2 ( 2 )^2 12 ] & ^ = M ^2 48 = 4 aligned Correct option is (2)

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