Moment of inertia, when a velocity of ball triples?

AI Thread Summary
The moment of inertia of a ball does not change when its velocity triples, as it depends solely on the mass and radius of the object, not its velocity. The formula for moment of inertia indicates that these factors are the only variables involved. While some discussions mention relativistic effects at high speeds, they are not relevant for typical scenarios. The consensus is that inertia remains constant under the conditions described. Understanding the fundamental definition and formula for moment of inertia is crucial for answering such questions.
rcmango
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Homework Statement



What happens to the moment of inertia when the velocity of a ball triples?


Homework Equations





The Attempt at a Solution



does the moment of inertia triple? become nin times bigger, remain the same, or become only 1/3 of what it was?

not sure, what is really going on with the inertia in this situation.
help please.
 
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The first question I would ask myself is:

What does the moment of inertia depend upon? Does it depend on the velocity?

Do you know what moment of inertia is and how it is defined? Do you know the formula for the moment of inertia of a solid sphere (or how to calculate it)? If so, you should be able to answer this question yourself.
 
okay, so i assumed that the inertia will stay the same because the radius and the mass are in the formula only.
 
rcmango said:
okay, so i assumed that the inertia will stay the same because the radius and the mass are in the formula only.

you are correct , though i think at relativistic speeds you get a mass dilation but i don't know jack about that
 

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