another interesting video

[mr_bojangles]

yes, they are assumed to be the same mass and size

thats what perplexed me, for i feel as if ive seen a single slope example where the ball reaches at the same time with the same momentum....

[mscoffman]

I suspect that how the mass is distributed within the radius
of the object has some effect on how much faster the one
course is run. The biggest difference probably occurs when
the object is a thin shell, like the cellulose ping-pong ball.
There is a large percentage of the mass of rotational momentum
as a fraction of forward momentum. A smaller difference
would probably occur if the objects were solid ball bearings
with a larger percentage of forward momentum to rotational
momentum. I doubt there is any difference based on absolute
weight or density, but on how that mass is distributed in terms
of the radius rotation.

So our surprise at the velocity difference is probably due to
the thin shelled nature of ping pong balls.

:S:MarkSCoffman