Recangular Prism: Moment Of Inertia

AI Thread Summary
The discussion centers on calculating the moment of inertia for a rectangular prism with dimensions 72 x 36 x 8 inches and an offset center of mass. The focus is on determining the turning radius in the length/width plane, as height is not a factor in this scenario. Participants express uncertainty about the calculations, particularly regarding the impact of the non-homogeneous material and the asymmetrical center of mass. While some equations from a textbook were referenced to address the moment of inertia, the primary goal is to find the turning radius based on the applied forces. The conversation highlights the complexity of the calculations due to the object's uneven weight distribution.
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There is a rectangular prism (L x W x H) = (72 x 36 x 8). The center of mass is 31 inches from one end lengthwise, and centered heightwise and widthwise.

I drew an image: http://www.xdemi.com/hovcalc/delirium.bmp

Basically, we need the moment of inertia of this object. Two forces are going to be applied at the top-back of the box-frame, and we want to calculate the turning radius. (This is for a hovercraft). We dont' really care about the height-direction. We just need turning radius in the length/width plane. So I suppose we can forget about the height factor.

What is the moment of inertia if the center of mass is offset lengthwise?

Actually, if you know how to calculate the radius or whatever just by knowing the forces and the information I gave you, then that'd be great. Because we could care less about the moment of inertia if we could find the radius of turning.
 
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Why is the CG offset on a symetric object? It is hard to tell from your diagram. Is it because it is not homogeneous material? Is the frame made of different members or is it one whole piece?

I am not familiar with any calculations regarding turning radius specifically. However, we can answer the moment of inertia problem.
 
It is not a evenly distributed weight, and not homogneous. However, we found some equations in a textbook that helped us. Thank you anyway.
 

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