Exactly! Thanks!
Exactly! Thanks!
Ken, thanks for pointing out the discrepancy. I re-checked and you were right.
No worries. Just glad that no one remembers my post from a couple years ago asking if a ball continued to gain speed after it was released!
sleepy,
One thing I noticed, and I'm not sure it matters, is that the MLB pitcher is using a splitter grip. In this case, it slowed the spin down to about 4 revolutions over the distance travelled. I'm wondering if the slow spin, combined with the orientation of the seams keeping that smooth side facing the batter made the difference. If the ball had been thrown with regular spin and with the same axis of rotation, I wonder if the effect would have been different?
The rough side heading into the air (the direction of velocity) acts like a brake kicking up a high pressure area on that side of the ball, while the rough side heading away from the air moves easier. The ball moves toward the smoother flow side and away from the higher pressure.
The same thing with the NASCAR roof flaps. They mess up the smooth air on top of the car when it gets backward. This make a higher pressure on top and prevents the car from lifting.