
61=2.4 ℓ=0.4m
sin60∘=ℓr
r=1sin60∘=2ℓ3
MOI, I=[12mℓ2+mr2]6
=[12mℓ2+m(2ℓ3)2]6
=5ml2
=5×1×0.16
=0.8
I=8×10−1kgm2
JEE Main 2021 — Physics Mechanics
A uniform thin bar of mass 6kg and length 2.4 meter is bent to make an equilateral hexagon. The moment of inertia about an axis passing through the centre of mass and perpendicular to the plane of hexagon is ___________ ×10−1kgm2.
Held on 24 Feb 2021 · Verified 6 Jul 2026.
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