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Topic: Hyperbolas in Nature
Replies: 29   Last Post: Mar 24, 2010 6:05 AM

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 John Conway Posts: 2,238 Registered: 12/3/04
Re: Hyperbolas in nature
Posted: May 12, 1996 2:40 PM

On 10 May 1996, C. Kenneth Fan wrote:

> I think I've got another one:
>
> Hold a large hoola hoop around yourself, look straight forward, and close one of
> your eyes. (Don't look down directly at the hoop, just view it vertically
> askance.) Then, chances are you'll have a hyperbola across your field of
> vision...If you've got just incredibly over-exagerated posture, you might
> catch a parabola, or even an ellipse, but for me, I'd end up cheating by
> tilting my head down or I'd break my back to see the ellipse this way.
>
> Ken
>

This one supposes that one's visual field has been identified with
a plane, which admittedly is the usual assumption, but usually it's
really being made only of a small portion of the visual field, and here
it's a large one, which would more naturally be identified with a
hemisphere (or, at least, SOME portion of a sphere).

John Conwaqy

Date Subject Author
5/3/96 Erica Morse
5/3/96 CALCCOCH@aol.com
5/3/96 Michael Thwaites
8/26/05 K.E.Raghav
8/26/05 K.E.Raghav
5/3/96 John Conway
5/3/96 John Conway
5/4/96 David Masunaga
5/5/96 Brian Hutchings
5/6/96 Lou Talman
5/6/96 John Conway
5/6/96 John Conway
5/7/96 Pat Ballew
5/9/96 Brian Hutchings
5/10/96 C. Kenneth Fan
5/12/96 John Conway
5/13/96 C. Kenneth Fan
5/13/96 Brian Hutchings
5/14/96 C. Kenneth Fan
5/15/96 C. Kenneth Fan
5/15/96 John Conway
5/16/96 Brian Hutchings
3/11/99 runa
5/9/00 Stephanie Ernst
5/11/00 mary krimmel
5/15/00 Niyeda
3/14/03 Erin
3/16/03 Terri Lynn
2/2/10 Jordyn Kabir
3/24/10 viewtech