Well, as has been previously beat to death, the RPM's do not increase. What happens is that the forward motion of the ball slows more quickly than does its rotation. That means that proportionally, rotation as compared to the forward motion continually increases until something gets in the ball's way.Larry's original question was:
Here is the question: Does the RB continue rotation of 1 turn every 4', or does it accelerate to a faster rotation?
The answer is: NO.
Perhaps the original question was spot on in concept.