No work is done by gravity on a bowling ball resting or moving on a bowling alley because...

No work is done by gravity on a bowling ball resting or moving on a bowling alley because the force of gravity on the ball acts perpendicular to the surface. But on an incline, the force of gravity has a vector component parallel to the alley, as sketch B shows. Discuss the two ways this component accounts for (a) acceleration of the ball and (b) work done on the ball to change its kinetic energy.