Finding Moment of Inertia for a Uniform Thin Solid Door

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To find the moment of inertia of a uniform thin solid door with dimensions 2.2 m height, 0.870 m width, and mass 23 kg, the formula I_{cm} = (1/12)M(width^2 + height^2) can be used. Calculus is not necessary for this specific problem, as the moment of inertia for a rectangular plate is a standard formula. The integration approach involves using the density and geometry to determine dm and the bounds of the integral. This method simplifies the calculation for the door's moment of inertia. The discussion concludes with confirmation that the solution is understood.
jmf322
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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!
 
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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.
 
Use the moment of inertia of an uniform rectangular plate

I_{cm} = \frac{1}{12}M(width^2 + height^2)
 
sweet thanks guy, i got it! laters
 
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