Re: HELP IN A HURRY!

[yanai@prism.bgu.ac.il (Yanai Krutman)]

Lammers,

First of all, I hope that the temperature at the plate is cte.; or in
other words that thermal equilibrium is already achieved.
If not the experiment will be more interesting, because you can show
the non-linear behaviour of the air refraction index Nair=
N0*factor(dT/dt),

> I AM DOING AN EXPERIMENT WITH MIRAGES.HERE IS THE BASIC IDEA


                / 
            /
> LASER---/
      __________
      |HOTPLATE|
      
> SORRY FOR THE ROUGH DIAGRAM. THE PROBLEM I AM HAVING IS YOU CAN 
> CONSIDER THE HOT AIR TO BE A DIFFERENT MEDIUM THAN THE AIR AT ROOM 
> TEMPERATURE SINCE THE DENSITY IS LESS. I AM USING SNELL'S LAW 
> n1 SIN01 =n2 SIN02

If a laser light has a speed larger then the light speed at he medium 2
you will see a cone at the light propagation direction like a
light induced( laser induced ) Cerenkov effect. see I. Golub, G.Erez
and R. Shuker at Appl.Phys.B, 31, 75(1983) and references therein.

Good luck!

Yanai


Yanai Krutman,
Senior Engineer
Ben-Gurion University of the Negev      Kupat Holim Klalit Health Services     
Faculty of Engineering                  Soroka Medical Center                  
Nuclear Engineering Department          Institute of Oncology
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Be'er Sheva  84105                      Be'er Sheva 84101
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email: yanai@prism.bgu.ac.il            phone: 972-7-400682
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