Does kinetic friction speed up or slow down an object? Therefore, which type of work is done by kinetic friction? What can you conclude about the change in an object’s speed relative to the type of work done on that object? !!!

Complete these sentences. if a roller coaster train has a potential energy of 1,500 j and a kinetic energy of 500 j as it starts to travel downhill, its total energy isj. once the roller coaster train gets closer to the bottom of the hill, its kinetic energy increases to 1,100 j, and its potential energy decreases to j. when the train reaches the bottom of the track and is traveling along the ground, its kinetic energy isj.