Moment of inertia time in physics, hard as hell concept, but heres the question:(adsbygoogle = window.adsbygoogle || []).push({});

You swing a small, heavy weight on the end of a light stick (the stick is light enough you can neglect its moment of inertia, and you can consider the weight as a point mass). Remember that the moment of inertia is a measure of how an object resists angular acceleration. How would the following actions effect the moment of inertia of what you are swinging

A) doubling mass of weight

B) adding an equal weight to the first at the center of the stick

C) adding a weight that is 4 times the original mass to the center

D) using a stick that isnt light, but weighs as much as the original weight on the end

so, im using the equation I = mr^2, for A i got that if you double the mass, the moment of inertia is doubled as well. for B i believe that if you add a weight to the center of the stick, it shouldn't really affect it because it is not a distance away from the axis of rotation, same thing with C. For D i put that the moment of inertia increases because you get mass stick * r^2 + mass weight * r^2.

Is what im saying here right? I think A and D are right but im quite unsure of B and C, any help would be appreciated

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# Homework Help: Moment of inertia ?s

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