Question

in rotatonal motion moment of inertia of an equilateral triangle

Answer 1

Moment of Inertia of the equilateral triangle depends upon the axis of rotation that is chosen
For example, if you choose your axis of rotation to be passing through any one particle.
Then , Momentum of Inertia = 2m*a^2
where m is the mass of the triangle and a is the length of the side of the equilateral triangle.
However, if you are taking your axis of rotation to be passing through any two of the vertices of the triangle then
Moment of Inertia = m/4*a^2

However, Moment of Inertia of any triangle where axis of rotation is passing through centre of mass will be
Moment of Inertia = mh^2/6
where h is the height of the triangle .

Hope this helps you !
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