A roller coaster car is moving at 20.0m/s along a straight horizontal track. what is the speed after climbing a 15.0m hill? neglect the effects of friction

Answer 1

The kinetic energy loss will equal the potential energy gain.
V1^2/2 - V2^2/2 = g H = 147 m^2/s^2
V1^2/2 = 200 m^2/s^2
V2^2 = 2*(200 - 147) = 106 m^2/s^2
V2 = 12.1 m/s