Question

Torques and Angular Momentum

1. A 250 kg playground merry-go-round has a radius of 2.0m and can be approximated as a disk.

A.Find the moment of inertia of the merry-go-round.

B.A 30.0 kg child applies 20 N tangential force for 10 seconds and then jumps on the edge while moving at the same speed as the merry-go-round. Find the angular speed of the merry-go-round and the child.

C.How much work did the child do on the merry-go-round?

D.How much average power did the child apply to the merry-go-round?

E.Treat the child as a point mass on the merry-go-round and find the total moment of inertia of child and merry-go-round.

F.The child walks to a point B, 1.0 meter from the center thereby changing the moment of inertia of the system. Find the new angular speed.

G.How much work did the child do to walk toward the center to point B?

Answer #1

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m2. When the merry-go-round is at rest, a 20 kg boy runs
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merry-go-round. The angular velocity of the merry-go-round is
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