Re: ....on "heating tape" idea

[herbgottlieb@juno.com (Herbert H Gottlieb)]

On Fri, 09 Oct 1998 09:41:00 CST ramirez@phys.physics.tamu.edu writes:
> Herb,
>
> I'll check for the thermistors, etc for you. This gets me to thinking on
how a computer can be used to do the measurements.
> Vernier used to sell a thermistor that could be interfaced with a
> computer. Now, if the expansion of the rod could be coupled with
> the change in temperature, the computer could be used to plot if
> the values are linear .The computer can be used to show a high(?) tech
way of demonstrating this.
>
OK ...Now we are really cooking!
My idea is to use the Michelson interferometer principle. Attach a mirror
over the end of an expansion rod at one leg of the interferometer and
adjust the other mirror to produce fringes on a screen.  As metal rod is
heated, the fringe shift can be detected with photocell connected to the
computer. This measures the expansion while your thermister measures the
temperature.   

Here is another good (and hi-tech) opportunity for a student project
using low-cost readily available materials. 

Herb Gottlieb from New York City
(Where we are always looking for student project ideas ....and here's
another one)