[Prev][Next][Index][Thread]
Re: 50%
Tesla List wrote:
>
> >From couturejh-at-worldnet.att-dot-netMon Nov 4 21:57:51 1996
> Date: Tue, 5 Nov 1996 01:36:25 +0000
> From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
> To: tesla-at-pupman-dot-com
> Subject: Re: 50%
>
> At 03:25 PM 11/4/96 +0000, you wrote:
> >From MALCOLM-at-directorate.wnp.ac.nzMon Nov 4 06:45:29 1996
> >Date: Mon, 4 Nov 1996 20:09:43 +1200
> >From: Malcolm Watts <MALCOLM-at-directorate.wnp.ac.nz>
> >To: tesla-at-pupman-dot-com
> >Subject: Re: 50%
> >
> >Wow! I just have to respond to this post on the 2 cap problem.....
> >
> >> Energy is conserved. Mistakes in capacitor circuit theory and
> >> algebra are the problem. That is why you did not remember it from
> >> college. The voltage across the two capacitors after the
> >> reconnection is not V/2. It is V/sqrt2. This can be easily checked
> >> by test and correct algebra.
> >>
> >> The voltage will be a little less than V/sqrt2 because there is
> >> some spark loss in the reconnection. In the test that I made the
> >> voltage across the two capacitors was slightly less than V/sqrt2
> >> because of losses but was still much more than V/2. Using V/sqrt2
> >> in the equation will give a total of 100% energy (50% in each) for
> >> the two capacitors if the algebra is done correctly.
> >
> >So we now have Q = 2C x V/sqrt2 when we started with Q = CV. I think
> >your result begs an explanation. If no energy is expended in
> >connecting the two caps, how did the extra charge separation come
> >about?
> >I have just this very minute done this experiment with two high
> >quality capacitors and the voltage comes to V/2 near as.
> >
> >Malcolm
> >
> -----------------------------------------
>
> Malcolm -
>
> V/2 New zealand
> V/sqrt2 San Diego
>
> The reason the reciprocals are different in New Zealand than in San Diego is
> because we are on different sides of the planet. (:>) (:]) (:<)
>
<SNIP>
Maybe something to do with Coreolis effect above and below the
Equator?? :^)
<SNIP
> This brings up the question. How did you measure the voltage in your test
> and come up with V/2? Was it a rough estimate? Was the voltage on the two
> caps a steady voltage or a reducing voltage? Were the caps equal, see below.
> I used 200000 uf and a digital meter and got a little under V/sqrt2 and
> greater than V/2. I found that smaller capacitors did not work very well to
> get the accuracy required using equal capacitors..
>
<SNIP>
I suspect this is the heart of the problem - An electrolytic cap's
capacitance is not fixed with respect to voltage, and an electrolytic
also exhibits significant "rebound" after being quickly discharged. If
you took a pair of high quality film capacitors I think you'd get
results that are closer to Malcolm's.
<SNIP>
-- Bert --