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

A mass distribution in the positive x region of the xy-plane and in the shape of a semicircle of radius a, centred on the origin, has mass per unit area k. Find, using plane polar coordinates, its moments of inertia about the x and y axes.

2. Relevant equations

3. The attempt at a solution

I know that I=∫r^2.dm

dm=k.dA=k.r.dr.dθ in polar coordinates.

So I=k∫dθ∫r^3.dr

But I'm not sure about the limits, or how to differentiate between the moments of inertia about the x and y axes.

Any help would be brilliant.

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# Homework Help: Moments of inertia by integration

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