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sci.math.independent  Topic: sphere Replies: 25   Last Post: Jul
3, 1996 11:38 AM  Advanced Search  Daniel A. Asimov  Posts: 101
Registered: 12/3/04 Re: sphere Posted: Jun 26, 1996 7:48 PM  In
article <31D15F98.5E90@dexp.com> Tim Helton <thelton@dexp.com>
writes: >I wish someone would explain in real world terms (that
I can visualize) >why a sphere's area is exactly equal to 4
circles of the same radius. >I'm losing alot of sleep trying to
do it myself :)   This is actually a fascinating question. Even
though it's easy enough to prove this using calculus, that
method doesn't provide much insight into WHY  (*) area(sphere) =
4 * area(disk)  where the radii of the sphere and disk are
equal.  * * *  Here is a bogus but amusing "proof" which may
just possibly be justifiable. (But probably not.)  Consider the
disk D(2r) of radius 2r. Since area magnifies by the square of a
linear magnificati