A 3.00-m-diameter merry-go-round is initially rotating with an angular speed of 1.65 rad/s. The merry-go-round is a solid, uniform disk with mass 120 kg. A child, 35.0 kg, and a parent, 65.0 kg, are standing at the edge. a) Because there are no rails on this merry-go-round, static friction provides the centripetal force. What minimum value for the coefficient of static friction between the child’s shoes and the merry-go-round surface is required to keep the child on the merry-go-round? (Apply Newton’s 2nd law in the radial direction.) b) What is the initial angular momentum of the system (merry-go-round+child+parent) about the central rotation axis? c) What is the initial rotational kinetic energy of the system

A 3.00-m-diameter merry-go-round is initially rotating with an angular speed of 1.65 rad/s. The merry-go-round is a solid, uniform disk with mass 120 kg. A child, 35.0 kg, and a parent, 65.0 kg, are standing at the edge. a) Because there are no rails on this merry-go-round, static friction provides the centripetal force. What minimum value for the coefficient of static friction between the child’s shoes and the merry-go-round surface is required to keep the child on the merry-go-round? (Apply Newton’s 2nd law in the radial direction.) b) What is the initial angular momentum of the system (merry-go-round+child+parent) about the central rotation axis? c) What is the initial rotational kinetic energy of the system

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