Calculating Moment Of Inertia

1. Oct 23, 2004

jmf322

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!

2. Oct 23, 2004

photon_mass

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.

3. Oct 23, 2004

Pyrrhus

Use the moment of inertia of an uniform rectangular plate

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

4. Oct 24, 2004

jmf322

sweet thanks guy, i got it! laters