A 25 kilogram boy on a playground swing moves with a speed of 4.5 m/s when the 3.0 meter long swing is at its lowest point. The mass of the swing seat is 2.0 kilogram. Neglect the mass of the supporting chains.
Find the angle that the swing makes with the vertical when the boy is at the highest point?
Suppose the boy could pump the swing really fast, compute what speed at the lowest point would be required for the boy to cause the swing to go in a complete circle around its support?