Quote:
Video-1 and Video-2 of a baseball striking an ash cylinder bolted to a concrete wall, taken at 1000 frames/s. These videos are best viewed with Windows Media Player. The grid in the background has a 1-inch spacing for both horizontal and vertical lines, allowing a calibration of the camera. In both cases, the incident ball has a speed of about 91 mph and a spin rate of 3000 rpm. In Video-1, the ball hits the top half of the cylinder, scatters upward, and emerges with backspin (i.e., the spin direction is unchanged). In Video-2, the ball hits the bottom half of the cylinder, scatters downward, and emerges with topspin (i.e., the spin direction is reversed). These video's and similar data are being studied to determine the relationship between the outgoing spin and the scattering angle.
http://webusers.npl.uiuc.edu/~a-nathan/pob/video.html
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3000 rpm should have some effect on the pitch height over the last 3 feet.
What did you see at 91 mph? Draw your own conclusion.
Hint: Use the mouse to play/pause video.