Date: Thu Oct 29 16:13:20 2009 ** **Back to Contents ** ------------------------------------------------------------------------ **

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Subject: Re: Weber-Kohlrausch experiment

Post:

Wolfgang,

I went through this set of experiments for a colloquium once. I called
it "Measuring c the hard way." I went from first principles to
calibrate volt and ammeters using a current balance and thermometry
and finally the parallel plate capacitor and ballistic galvanometer.
It all worked well but gave me an appreciation of how far we've come.
After all, we don't measure c anymore: it's a definition. If I look
around maybe I can find my notes (this was a couple of decades ago, I
think.)

Cliff

Quoting Wolfgang Rueckner :

> I'd like to attempt the 1856 experiment of Wilhelm Weber & Rudolph
> Kohlrausch in which they unified electric and magnetic phenomena and
> made the connection with light. This is the work that enabled Maxwell
> to predict the propagation velocity of electromagnetic waves. To
> potentially save myself time in "re-inventing the wheel," I am curious
> if anyone out there has already done this and can share tips on the
> do's and don'ts. Or, if you know of a published paper on this (in one
> of the educational journals), references are appreciated too. --
> Wolfgang





From tap-l-owner@lists.ncsu.edu Thu Oct 29 16:13:20 2009
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