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A playground merry-go-round of radius ? = 2.0 m has a moment of inertia ? =...

A playground merry-go-round of radius ? = 2.0 m has a moment of inertia ? = 250 kg ⋅ m^2 is rotating at 15 rpm about a frictionless, vertical axle. Facing the axle, a 25-kg child hops onto the merry-goround and manages to sit down on the edge. (a) (10 pts) What is the total angular momentum of the ‘merry-go-round-child’ system before and after the child hops on the the merry-go-round? (b) (10 pts) What is the new angular speed, in rad/s, of the merry-go-round? (c) (5 pts) How many seconds will it take for the system to cover 5.0 complete revolutions? (d) (10 pts) What is the total kinetic energy of the system before and after the child hops on the the merry-go-round?

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