Re: pinhole CD spinners

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From: John & Jan (johnjan@lahr.org)
Date: Tue Aug 20 2002 - 21:32:06 PDT 

Message-Id: <5.1.0.14.2.20020820223014.020d6b30@mail.attbi.com>
Date: Tue, 20 Aug 2002 22:32:06 -0600
From: John & Jan <johnjan@lahr.org>
Subject: Re: pinhole CD spinners

You can make a top from a CD by pressing a heated penny into the
center hole of the CD. This is describe here in terms of optical illusions.
http://jjlahr.com/science/Illusions/fbkspin.html

The case is not involved, so this is probably not what you are looking
for.

Cheers,
John

At 09:26 PM 8/20/2002 -0700, you wrote:
>Does anyone remember how to turn old CD's w/ cases into spinners for a math
>class? I saw someone do it at RAFT years ago, and I can't remember how it
>was done.
>
>Many thanks,
>
>g
>
>
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John C. Lahr
1925 Foothills Road
Golden, CO 80402
Phone: (303) 215-9913
john@lahr.org
http://jjlahr.com/science

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