A ball rolling on a smooth, horizontal surface (with no friction) has uniform motion or constant speed, as evidenced by the evenly spaced images of the ball in the stroboscopic photograph.
(A ball; rolling; L:on a smooth, horizontal surface) (A ball rolling on a smooth, horizontal surface (with no friction; has; uniform motion or constant speed)
A ball A ball rolling on a smooth, horizontal surface (with no friction
rolling has
L:on a smooth, horizontal surface
uniform motion or constant speed