Angela the puppy loves chasing tennis balls, so her owners built a tennis ball launcher. It fires balls along the floor at some initial speed, applying no rotation to them. The balls initially slip along the floor, then start rolling without slipping. Ignore the potential deformation of the ball and floor during this process, as well as air resistance.
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Question:
There are three kinds of balls that can be launched in this set-up, all having the same radius R:
I. a regular tennis ball (a thin spherical shell of rubber) of mass m1.
II. a solid wooden ball of mass m2.
III. a solid rubber ball of mass m3.
where m1<m2<m3. All three types of ball emerge from the launcher with the same velocity. For which ball will the final velocity be highest?
(A) Ball I.
(B) Ball II.
(C) Ball III.
(D) Balls II and III.
(E) The final velocity will be the same for all three balls.