Date: Fri, 27 May 2005 13:32:14 -0400

Author: Gerald Zani

Subject: Re: TIR Demo


I do it with a tall graduated cylinder.

A notch is good but it is not necessary. I do it without a notch in the
cylinder. -- JZ

At 11:34 AM 5/27/2005, you wrote:
>A professor wants a demonstration of total internal reflection. The idea
>is to point a laser at an angle towards a notch in the top of a plastic
>cylinder. The laser light then spirals down around the cylinder. The
>cylinder should be big enough for a classroom to see it-about 30 cm tall,
>20 cm diam.
>Are there any suggestions about how to build one, such as, type of
>plastic, minimum thickness of cylinder, any other consideration.

Gerald Zani e-mail:
Manager of Demonstrations phone: (401) 863-3964
Department of Physics FAX: (401) 863-2024
Brown University Providence, RI 02912-1843 USA

Do a little more of that work which you have confessed to be good,
Which you feel that society and your most Just Judge rightly demand of you.
Cultivate the tree which you have found to bear fruit in your soil.
If you have any experiments you would like to try, try them.
Now's your chance.

Henry David Thoreau, Journal entry, 1850.

From Fri May 27 13:30:32 2005