# A ball rolls off a flat surface on to a road that slopes downwards. Which one of the velocity-time graphs (A, B, C, or D) would be an appropriate representation of the ball's motion as it rolls across the horizontal surface and then down the incline? Consider frictional forces.

The ball will slow down due to friction while moving across the level surface and it will speed up due to the parallel component of the weight vector while moving down the incline. Graph D depicts both of these features.