Simple rotational motion problem

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When two identical merry-go-rounds, one crowded with children and the other nearly empty, cut off their motors simultaneously, the one with the children will take longer to stop. This is due to its larger mass, which increases its moment of inertia. Both merry-go-rounds experience the same friction, but the heavier one has greater angular momentum. Consequently, it requires more force to bring it to a halt. The discussion emphasizes the relationship between mass, moment of inertia, and angular momentum in rotational motion.
kirby27
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Two identical merry-go-rounds are rotating at the same speed. One is crowded with riding children; the other is nearly empty.

If both merry-go-rounds cut off their motors at the same time and coast to a stop, slowed only by friction (which you can assume is the same for both merry-go-rounds), which will take longer to stop?

i think the one with the people will take longer to stop because they have the same moment of inertia but the mass of the people one is larger.
 
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I'd agree with you. If the force of friction is the same, and the speed is the same, the heavier merry-go-round will have more angular momentum. Therefore it will take more force to stop it.
 

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