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Old 10-09-2012, 11:40 AM   #368
Bionic Poster
Join Date: Oct 2005
Posts: 34,394

Originally Posted by 5263 View Post
Not sure what you have in the corner there, but

I ask anyone, from Nalbanian's view,

Is his racket moving clockwise or counter clockwise?
From Fatbandian's view, it is moving counter clockwise. At contact, it is POSSIBLE that this motion combined with the upwards motion produces clockwise rotation on the ball if it contacts the lower left of the ball.

Give a globe a spin by swiping your hands anti-clockwise wrt yourself. The globe will spin clockwise wrt you.

A simpler visualization (gleaned from helping my son in the new Principles of Engineering course they are pushing these days in high school): meshed gears spin in opposite directions.

Again, I am not sure if Fatty is contacting the ball upwards on the lower left edge, but if he is, that is what toly is saying.
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