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Question
Let IA and IB be moments of inertia of a body about two axes A and B respectively. The axis A passes through the centre of mass of the body but B does not.
Options
IA < IB
If IA < IB, the axes are parallel
If the axes are parallel, IA < IB
If the axes are not parallel, IA ≥ IB
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Solution
If the axes are parallel, IA < IB
If axes A and B are parallel, we get
\[I_B = I_A + m r^2\]
Here, r is the distance between two axes and m is the mass of the body.
\[\therefore l_A<l_B\]
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