Hi, I'm in the middle of programming an inertia system and am only really just starting to appreciate what the heck inertia is :) I have been taught inertia, but I haven't actually applied it in a real situation (all my exams and tutorials have resulted in formulae giving answers like 2/7Ma^2).(adsbygoogle = window.adsbygoogle || []).push({});

So I've written a function to find inertia of a sphere and I've plugged some numbers in. I'm a bit confused over what formulae to use for starters.

I can sorta see that inertia of the spheres centre might be useless? given that they're totally symetrical? Am I off with this?

For inertia of a sphere about the diamater I'm using the equation 2/5 Ma^2. Is this appropriate?

Also I've plugged in numbers (like I said). I've never got a numerical answer for a system before so I'd appreciate some guidance as to wether or not I'm correct.

sphere at 0,0,0

radius 2

mass 1

rotation about point on diameter

2/5 Ma^2

0.4 * 1 * 4

MI = 1.6 ?

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# Homework Help: Moments of Inertia

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