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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 ‘ α ’. 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 :

1. α /4
2. α /2
3. α /8
4. α

Correct answer: α /4

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