3 A child of mass 20 kg on a swing hanging from a 3.0m chain is pulled by her uncleuntil the swing is at an angle of 30 degrees to the vertical.a) How much farther from the ground is the child now, compared to when the swing washanging straight down?b) Since the child is motionless at he beginning and the end of the process, what can yousay about the work done by gravity, and the work done by the puller on the child duringthe pullback?What is the amount of work her uncle does to pull back the swing?c) If he lets the swing go at this point, what is the child's speed as she passes the lowestpoint of the swing & the chain is vertical? Ignore the mass of the swing seat & chain.

We are given a child on a swing. We are given mass of the child. We are given the length of chain of…

Answered: 3 A child of mass 20 kg on a swing…

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1. A 23.0 kg child is playing on a swing with a length of 2.5 m. If the swing starts from rest and makes an angle of 40.0◦ with the vertical at the top of the swing, a) determine the child’s speed at the bottom of the swing neglecting friction. b) If the swing has a speed of 2.8 m/s at the bottom, determine the work done by friction during the downswing and, bonus) assuming the force of friction is constant, determine the maximum angle the swing attains on the upswing after passing through the bottom. Hint: Use the approximation that cos θ ≈ 1 − 1 2 θ 2 for angles given in radians.