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Mechanics
Easy
Question
The moments of inertia of a thin square plate ABCD of uniform thickness about an axis posing through the centre 0 and perpendicular to the plate are
(where /2, 1 and 14 are, respectively, the moments of inertia about axes I, 2, 3 and 4, where axes are in the plane of the plate)
- all the above
The correct answer is: all the above
According to the theorem of perpendicular axis: Moment of inertia of the plate about an axis passing through centre 0 and perpendicular to the plate is I0 = I1+I2 =I3+I4 (Because diagonals 1 and 2 as well as 3 and 4 are mutually perpendicular) Now, according to symmetry,
For a square plate,
Hence 
i.e option 1,2&3 are correct.
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