Is a balls ability to bounce several times affected by the height from which it is dropped

Question

Hypothesis

Answer 1

Hi Ray:

 

Physically speaking, yes.  A ball held higher starts with more mechanical energy.  Each time it bounces off the ground, it loses a little of that mechanical energy (which is converted to to sound energy, to create the sound you hear, to heat energy by the frictional contact with the ground, and other outlets).  So it bounces back up with less mechanical energy than when it hit.

 

Each time it bounces again, it loses more of that mechanical energy.  So, all else being equal, if it starts with more mechanical energy, it will be able to bounce more times (assuming, as is approximately true, that the mechanical energy lost in each bounce is not also significantly affected by height, which is a reasonable approximation over a good range of reasonable heights).

 

The number of bounces is also affected by other factors, of course.  Chief among them are the nature of the ball (particularly, a quantity called "elasticity") and the type of material it is bouncing off of.  A superball will bounce more off the same surface, typically, than a beanbag ball.  And you will get more bounces for a ball, typically, off a hard floor than a carpet.

 

But, along with factors like these, height of drop should affect the number of bounces (assuming the surface is strong enough to provide a force to cause a bounce; don't drop a bowling ball from too high onto a hard floor, unless the floor is one you can afford to damage).

 

Sounds like an experiment can be done to test this hypothesis. :)