Re: Z-Machine Sparkage- Try this at home!!

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jolyon Vater Cox by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jolyon-at-vatercox.freeserve.co.uk>


 >
 > --- Tesla list <tesla-at-pupman-dot-com> wrote:
 >  > Original poster: "brianb by way of Terry Fritz
 >  > <teslalist-at-qwest-dot-net>" <brianb-at-antelecom-dot-net>
 >  >
 >  > Sue/all,
 >  >
 >  > I repeated your experiment and noticed some
 >  > interesting things happening in
 >  > the gap area. Some of these observations may be of
 >  > use for our Tesla Coil
 >  > gaps so I don't think this is to far off topic.
 >  >
 >  > My setup used a .06uf capacitor, 12kv-at-30ma NST, .75"
 >  > brass electrode, and
 >  > .25" gap between the electrode and the water.
 >  >
 >  > One of the things I noticed was the physical wave
 >  > created in the water each
 >  > time the gap fired. At first I assumed it was due to
 >  > the shockwave from the
 >  > superheated air in the arc channel (which also made
 >  > an acoustic "pop" each
 >  > time the gap fired). Upon closer examination I
 >  > noticed this was only part of
 >  > what was happening. What I observed was the water
 >  > under the gap being pulled
 >  > up towards the electrode due to electrostatic forces
 >  > then dropped as the gap
 >  > fired (dissipating the charge). This electrostatic
 >  > effect is quite
 >  > pronounced as I'm able to observe the gap distance
 >  > being reduced by over
 >  > half.
 >  >
 >  > I had made an assumption that the breakdown voltage
 >  > was simply due to the
 >  > static distance between the electrode and the
 >  > water's surface. But what I
 >  > found was a dynamic interaction between the gap
 >  > voltage and the
 >  > electrostatic forces. As the voltage is increased
 >  > the electrostatic forces
 >  > pulled the water up closing the gap distance until
 >  > it fires.

I have noticed this -though less spectacularly- in a Kelvin water-drop
electrostatic generator
-the strong attraction of dissimilar charges causes the droplets to attach
themselves to the induction rings and the spark gap, while they are repelled
by the  similar charges on the collecting pans;  a water drop attached to
one of the conductors in the gap  -but not quite bridging it- pulled itself
into a cone and touched the other conductor before collapsing as the charge
dissipated; the cycle then repeated.

Jolyon