A 28.0kg child plays on a swing having support ropes that are 2.10m long. A friend pulls her back until the ropes are 43.0%u2218 from the vertical and releases her from rest.
part a What is the potential energy for the child just as she is released, compared with the potential energy at the bottom of the swing?
part b How fast will she be moving at the bottom of the swing?
part c How much work does the tension in the ropes do as the child swings from the initial position to the bottom?