How Do You Calculate the Center of Mass for a Non-Uniform Object?

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To calculate the center of mass for a non-uniform object, such as a solar car shell, calculus is required to integrate the mass-weighted average position of its components. For uniform shapes, the center of mass aligns with the geometric center, but for non-uniform objects, it shifts towards the denser areas. A practical approach for complex shapes involves using computer software for numerical calculations or creating analytical approximations. SolidWorks is suggested as a potential tool for this purpose, as it includes a motion analysis feature. Accurate determination of the center of mass is crucial for the design and stability of the solar car.
crowajordan
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Could anyone help me figure out a formula to calculate a Center of mass for a non uniform object. In my case it would be a "shell" that would go over a body of a solar car. If anyone could help me that would be great.
 
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Hi crowajordan, welcome to PF!

You just have to use a little calculus to calculate the http://en.wikipedia.org/wiki/Center_of_mass" .

The 'center of mass' is the mass-weighted average position of an object. If you have a uniform, symmetric object: the center of mass is at the geometrical center (e.g. the center of a sphere). If one part was more massive than another (e.g. one hemisphere heavier) then the CoM would be displaced in that direction.

For a complicated object, you have to add up (integrate) over every piece ("differential element") of the object to find the center.

For a complicated real-life object, like a car-shell, you would either need to make a computer-program to calculate it numerically; or make some some sort of analytical approximation to the shape.
 
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Thanks for responding. Do you have any thoughts on a program that would be able to do that? Would Solidworks do?
 
I'm not familiar with programs like that, but I think solidworks should be able to do it. They have some sort of 'motion analysis' macro I believe. Google will know.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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