I just have some questions about kinetic energy. 1. If you are going up an incline on a roller coaster and you are trying to calculate the KE lost; is it possible to use this to find the velocity at the top, or does this only apply to downwards motion? 2. Can you apply the power formula to a roller coaster going down an incline, or is this only useful for when a motor is in charge of the energy outlay rather than gravity? 3. Can you use GPE and KE, even if you are on an incline/slope?