Conservation of Angular Momentum Video Lessons

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Problem: A playground merry-go-round of radius R = 2.00 m has a moment of inertia I = 250 kg•m2 and is rotating at 10.0 rev/min about a frictionless, vertical axle. Facing the axle, a 25.0-kg child hops onto the merry-go-round and manages to sit down on the edge. What is the new angular speed of the merry-go-round?

FREE Expert Solution

We have jumped onto a rotating system along the radius. Adding mass changes the moment of inertia of the merry-go-round. The angular momentum of the system is conserved.

Conservation of angular momentum:

L1=L2

Angular momentum:

L=Iω where I is the moment of inertia and ω is the angular speed.

Moment of inertia of a point mass:

I=mr2

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Problem Details

A playground merry-go-round of radius R = 2.00 m has a moment of inertia I = 250 kg•m2 and is rotating at 10.0 rev/min about a frictionless, vertical axle. Facing the axle, a 25.0-kg child hops onto the merry-go-round and manages to sit down on the edge. What is the new angular speed of the merry-go-round?

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What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Conservation of Angular Momentum concept. You can view video lessons to learn Conservation of Angular Momentum. Or if you need more Conservation of Angular Momentum practice, you can also practice Conservation of Angular Momentum practice problems.

What textbook is this problem found in?

Our data indicates that this problem or a close variation was asked in Physics for Scientists and Engineers - Serway Calc 9th Edition. You can also practice Physics for Scientists and Engineers - Serway Calc 9th Edition practice problems.