Prove Rotational Inertia of Uniform Sphere is 2/5MR^2

Thread starter bluejay18
Start date Oct 27, 2005
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Inertia Rotational Rotational inertia

AI Thread Summary

To prove that the rotational inertia of a uniform sphere is 2/5MR² about any axis, one can start by considering the sphere's volume and its geometric properties. A useful approach is to model the sphere as an infinite number of overlapping cylinders, which simplifies the calculation of mass distribution. This method allows for the integration of mass elements to derive the moment of inertia. Understanding the relationship between the sphere's geometry and its rotational properties is crucial for the proof. The discussion emphasizes the importance of foundational concepts in geometry and physics for solving such problems.

Oct 27, 2005

bluejay18

How would I prove that the Rotational Inertia of a unform sphere is 2/5M(R)squared, about any axis?

I have no idea where to start. . .

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Nov 11, 2005

vaishakh

how did you findratational inertia of others?
reply to this first

i think you migh be knowing the method to find sphere volume. similarly consider sphere as a overlapping of inginite cylinders.

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