3 A child of mass 20 kg on a swing hanging from a 3.0m chain is pulled by her uncle until 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 was hanging straight down? b) Since the child is motionless at he beginning and the end of the process, what can you say about the work done by gravity, and the work done by the puller on the child during the 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 lowest point of the swing & the chain is vertical? Ignore the mass of the swing seat & chain.

3 A child of mass 20 kg on a swing hanging from a 3.0m chain is pulled by her uncle until 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 was hanging straight down? b) Since the child is motionless at he beginning and the end of the process, what can you say about the work done by gravity, and the work done by the puller on the child during the 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 lowest point of the swing & the chain is vertical? Ignore the mass of the swing seat & chain.