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Old Sun Aug 16, 2009, 06:52am
bob jenkins bob jenkins is offline
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Join Date: Aug 1999
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Quote:
Originally Posted by BillyMac View Post
It does? Don't you mean a right cylinder?
No, he doesn't. The "right" means that the "ends" of the finite section are perpendicular (at a "right angle") to the "sides".

In theory, a cylinder is analogous to a line -- it has no end points. As the rest of the quote shows, in practice, it's used as being analogous to a line segment.


IIRC (I don't have the books with me) the rule on "passing through" doesn't mention the cylinder. The only rule that does has to do with BI (and it uses a pharase like "the cylinder, the bottom end of which is the rim." So, rather than JohnnyRingo asking, "the ball needs to leave the cylinder?," he should have asked, "the entire ball needs to enter the cylinder?"
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