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Question
A body having its centre of mass at the origin has three of its particles at (a,0,0), (0,a,0), (0,0,a). The moments of inertia of the body about the X and Y axes are 0⋅20 kg-m2 each. The moment of inertia about the Z-axis
Options
is 0⋅20 kg-m2
is 0⋅40 kg-m2
is \[0 \cdot 20\sqrt{2}\]kg-m2
cannot be deduced with this information
Solution
cannot be deduced with this information
Ix = m2a2 + m3a2 = 0.20 ......(1)
Iy = m1a2 + m3a2 = 0.20 ......(2)
Iz = m1a2 + m2a2 ......(3)
We have three equations and four variables. So, Iz cannot be deduced with the given information.
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