1. The problem statement, all variables and given/known data The carriage and its passengers start at rest at A. At B, the bottom of the ride, the maximum speed of the carriage is 20ms-1. The vertical distance between A and B is 110m. The length of the track between A and B is 510m. The mass of the carriage and the passengers is 4000kg. By considering the energy changes from A to B, determine the average frictional force acting on the carriage. 2. Relevant equations 3. The attempt at a solution GPE at A = mgh = 4000 * 9.81 * 110 = 4316400 J KE at B = 0.5 * 4000 * 202 = 800000 J 4316400 - 800000 = 3516400 J work done. W = Fx. 3516400 = F * 510 F = 6900 N?