I'm a bit confused by the physics of the mountain car problem. The problem concerns driving an underpowered car up a mountain. I had expected that the car would be able drive up to a point where the forward force due to acceleration is equal to the opposing force due to gravity and that the car would then just stop. However, I am finding that the car falls back down and goes up the other slope, and continues to oscillates in that way. What am I misunderstanding? Here are the equations. The landscape curve is given by, cos(3*(x+(pi/2))), where x is the position. And, Velocity = Velocity + (Action) * 0.001 + cos(3 * Position) * (-0.0025) Position = Position + Velocity where Action = 1 and starting position = -0.5, which is the bottom of the valley.