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Topic: Calculating the area of a closed 3-D path or ring
Replies: 23   Last Post: Mar 25, 2013 4:54 PM

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 Shmuel (Seymour J.) Metz Posts: 3,473 Registered: 12/4/04
Re: Calculating the area of a closed 3-D path or ring
Posted: Mar 13, 2013 12:26 PM
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In <513FD11E.93AEB9D8@guy.com>, on 03/12/2013
at 09:06 PM, Math Guy <Math@guy.com> said:

>Looking for some thoughts about how to understand this problem.

There is no such thing as the area of a ring.

>a) if a membrane was stretched across the ring, what would the area
>of the membrane be?

A surface with zero variation, but not necessarily with minimal area.

>b) if the ring represented an aperture through which some material
>(gas, fluid) must pass, or the flux of some field (electric, etc).
>This would be Area B.

I believe that the flux would depend on the physical setup, not just
on the ring itself.

>I can imagine that summing the area of individual non-over-lapping
>triangles will give me "an area". Given 9 perimeter points it is
>possible to arrange more than one set of non-over-lapping triangles,
>with each set giving it's own total area - but which one is the
>"correct" one if they give different results?

Why would any peicewise linear surface be "correct"? It certainly
won't be minimal.

>Comments?

You need to ask a precise question in order to get a precise answer.
Define what you mean by the surface associated with the ring and
someone may be able to point you to an algorithm for calculating the
area.

--
Shmuel (Seymour J.) Metz, SysProg and JOAT <http://patriot.net/~shmuel>

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Date Subject Author
3/12/13 Math Guy
3/13/13 Ray Koopman
3/13/13 Nicolas Neuss
3/13/13 Peter Spellucci
3/13/13 Shmuel (Seymour J.) Metz
3/13/13 Frederick Williams
3/13/13 Brian Q. Hutchings
3/14/13 fom
3/14/13 fom
3/14/13 Math Guy
3/15/13 Ray Koopman
3/15/13 Math Guy
3/15/13 fom
3/16/13 Ray Koopman
3/16/13 fom
3/16/13 Math Guy
3/16/13 fom
3/16/13 Ray Koopman
3/15/13 Peter Spellucci
3/16/13 Math Guy
3/17/13 Ray Koopman
3/17/13 Math Guy
3/18/13 Ray Koopman
3/25/13 Gib Bogle

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