A uniform equilateral triangular lamina of side a has mass m. Its moment of inertia about the axis passing through the centroid and prependicular to the plane of the lamina is :-
A
`(2ma^(2))/(3)`
B
`(ma^(3))/(3)`
C
`(ma^(2))/(6)`
D
`(ma^(2))/(12)`
Text Solution
Verified by Experts
The correct Answer is:
A
Any uniform triangular lamina can be represented by three point masses for purpose of calculation of moment of inertia. Required moment of inertia `=3xx[(m)/(3)((a)/(2sqrt(3)))^(2)]=(ma^(2))/(12)`
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