Question

Consider a simple frictionless roller-coaster. It begins at x = 0, at a height of y = H. Then it drops into a dip, reaching a minimum at x = 100, with zero height (y = 0). Finally, it goes back up at x = 200, but only reaches a height of y = H/2. Assume the roller-coaster car starts from rest at x = 0. Which of the following statements are true?

A.The car's maximum gravitational potential energy occurs at the start, at x = 0

B.At the end, at x = 200, the car has only kinetic energy

C.Mechanical energy of the roller-coaster is not conserved because of the presence of the normal force

D.At the end, at x = 200, the car has the same total energy that it began with

E.In the middle of the dip, at x = 100, the car has both gravitational potential energy and kinetic energy