# A little boy stands at the bottom of an inclined road and kicks a soccer ball. The ball rolls northward up the driveway and then rolls back to the ball. Which one of the following velocity-time graphs (A, B, C, or D) most accurately portrays the motion of the ball as it rolls up the driveway and back down?

$\begin{array}{1 1}A\\B\\C\\D\end{array}$

Initially, the ball has a northward velocity and is slowing down. For an instant in time, it has a zero velocity. Then the ball moves with a southward velocity (i.e., in the opposite direction) and speeds up. At all times the ball has a "negative" (southward) acceleration. These features are all depicted in Graph D.