# Moments of Inertia about an axis

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Given an object with center of mass (0,0,0). What would be the simplest way to describe its moments of inertia about any axis. IE data stored so that the moments of inertia can be found in a simple manner without knowing anything about the object besides its mass.

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AFAIK, the only way to store the complete moment of inertia information about an object is with a tensor, called an "inertia tensor."

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Quote:
 Inertia - The tendancy of a body to preserve its state of rest or uniform motion unless acted on by an external resultant force.

A moment of inertia is just the rotational form of normal inertia. A measure of how readily an object spins, and is proportioanl to the mass of the object and where the force is applied ( often easiest to imagine as a force applied to a bar that is free to rotate, the moment of inertia is proportional to both the mass of the bar and where along its length you apply the force).

If you only have mass, then assume unit length. Like a unit vector.

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Oh, i forgot the equations :)

Clicky!

(damn wheres my pi icon gone!)

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Inertia tensors seem nice, thanks.

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