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jmf322
Oct23-04, 05:55 PM
Can someone point me in the right direction on how to find the moment of inertia of a uniform thin solid door, height 2.2 m, width .870 m and mass 23 kg. Do I need to use calculus to solve this type of problem? thanks!

photon_mass
Oct23-04, 07:05 PM
moment of inertia = Integrate[r^2 dm] where dm is given by a density * an appropriate differential. r is perpendicular distance from the mass element to the axis of rotation. the bounds of the integral and the dm are given by the geometry of the problem.

Pyrrhus
Oct23-04, 07:14 PM
Use the moment of inertia of an uniform rectangular plate

I_{cm} = \frac{1}{12}M(width^2 + height^2)

jmf322
Oct24-04, 12:33 PM
sweet thanks guy, i got it! laters