Quite good
It would be better, just to update the other file, instead of making a new one. Don't overflow NG. Your physics are not bad. I mean its a start. You use inertia. So, you need at least 4 vars, to describe the movement of the ball.
If you stick to it, you could do (even) better.
I like it cause I think there should be more physics in flash games! Otherwise, I would say, you need to make it more a game.
I like to see how old you are, but you dont have a profile.
Komix