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reflecting disks photo gallery   Message List  
Reply | Forward Message #49 of 84 |
Re: [curves_surfaces] reflecting disks photo gallery

There was a toy that had a virtual pig floating in air. There was an
actual pig at the base of the toy and his virtual image was at the focus
of a parabolic mirror. I believe the toy had two parabolic mirrors
sharing a focus.


Xah Lee wrote:
> just created this page:
> http://xahlee.org/Whirlwheel_dir/reflecting_disks/reflecting_disks.html
>
> a photo gallery of reflecting disks. (radio dishes, solar dishes)
>
> Xah
>
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--
Hop David
http://clowder.net/hop/index.html




Sat Apr 23, 2005 8:29 pm

hollister_david
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Message #49 of 84 |
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just created this page: http://xahlee.org/Whirlwheel_dir/reflecting_disks/reflecting_disks.html a photo gallery of reflecting disks. (radio dishes, solar...
Xah Lee
p0lyglut
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Apr 23, 2005
5:03 pm

There was a toy that had a virtual pig floating in air. There was an actual pig at the base of the toy and his virtual image was at the focus of a parabolic...
Hop David
hollister_david
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Apr 23, 2005
8:31 pm

yes i remember seeing that in Nature store. I thought i saw it on wikipedia too... but anyway they have a good article on mirage ...
xah lee
p0lyglut
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Apr 24, 2005
3:32 pm

Better to say Reflector dishes instead of reflecting disks. The TV dish receiver is not necessarily parabolic, since the focus is below the center of the dish...
Narasimham Gudipaty
glnarasimham
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Apr 24, 2005
2:50 pm

... I took your advice. ... if that means the surface is a surface of revolution. If so, the focus must be in the center. But that TV disk has the receiving...
Xah Lee
p0lyglut
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Apr 24, 2005
6:10 pm
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