Originally Posted by RedsManRick
The physics involved are basically lift. So you basically get a measure relative to what would have happened differently than if it was only gravity affecting it. The spin in the ball affects the flow of air around it. For a fastball with backspin, this creates a pocket of low pressure above the ball, which results in a small amount if lift - same principal as a plane's wing.
So instead of falling 40 inches it only falls 34 inches, meaning it had 6 inches of "rise".
(I know you probably know that, was for everybody's benefit)
I didn't know this (other than a rising fastball is actually on that does not sink as much). I had no idea it was a product of lift. I never really thought about the why... I think my best guess would have been that the seams acted like miny paddles and a spin grabbed the air causing the lift. I am clearly no physic guy.
... so Thank you. This was certainly to MY benefit.