III. Solving problems using energy bar charts. Using the method delineated in this tutorial, solve the following problems. A. Mary's 40 kg brother is at rest on a swing 0.50 m off the ground. Initial and final situation + forces She pulls him up until he is 2.0 m off the ground and releases him. How fast is her brother moving after he passes the bottom and has gone up to 1.5 m off the ground? KEi Ugi Usi Wother AEth KEr Ugf Usf B. A car moving at an initial speed vi applies its brakes and skids for some distance until coming to a complete stop. If the coefficient of kinetic friction between tires and the road is ux what distance did the car skid? Initial and final situation + forces KEi Ugi Usi Wother AEth KEr Ugf UsfC. A box (m = 2 kg) is moving upward at v = 5 m/s. A student is pulling the box up via a rope using a force of F = 30 N and Initial and final situation + forces applies the force for a distance of d = 5 m. How fast is the box moving after it has traveled 5 m? KE; Ugi Usi Wother AEth KEr Ugf Usf D. You are pushing a box (m = 4 kg) starting from rest horizontally with a constant force F = 30 N. After pushing it for a distance d = 5 m, the box reaches a hill inclined at 0 = 25. You stop pushing the box as soon as it reaches the hill. The coefficient of kinetic friction between the box and the road is ux = 0.4 and the hill is frictionless. How far up the hill is the box going to go? Initial and final situation + forces KEi Ugi Usi Wother AEth KEr Ugf Usf