A 1000 kg roller coaser train is intially at the top of a rise, at point A. It then moves 135 ft, at an angle of 40 degrees below the horizontal, to a lower point B.
Choose the train at point B to be the zero configuration for gravitational potential energy. Find the potential energy of the roller coaster-Earth system at points A and B, and the change in potential energy as the coaster moves.
The Attempt at a Solution
Y at Point A=86.8 m
Ug= 850640 Kj
This isn't the right answer, so where am I going wrong?