(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the moment of inertia of triangular prism (equilateral triangles with side 2a, parallel to xy-plane), mass M. It's centered at the origin with long side parallel to z-axis. Find moment of inertia about the z-axis, and without doing integrals explain two products of inertia (Ixy, Ixz, I suppose)

2. Relevant equations

The integral equation for Izz=int[(M/V)*(x^2+y^2)dV]

where V=volume, or in cylindrical coords. we can write (x^2+y^2)=r^2, where r=distance from z-axis

3. The attempt at a solution

I just can't figure out - if I do it in cartesian coords - what limits of x and y should I substitute? It doesn't look like it should be -a to a, since that wouldn't be geometrical center, and plus to that - it's a triangle, not square - so I should connect x to y somehow.... Or should I do it in different coord. system?...

Thanks a lot in advance!

I understand that this is easy question, but I just can't figure it out for some reason....

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# Moment of inertia of triangular prism

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