Re: Parallel and Series LCR Circuit Qs

["Jim Lux" <jimlux-at-jpl.nasa.gov> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Even in a low pressure chamber (not really vacuum, but in the 1 torr area)
you still get forked arcs. The chamber and stuff was cleaned quite
thoroughly before pumping down, the chamber was evacuated fairly well, and
then backfilled to the required pressure.  Dust would have a hard time
remaining airborne without any air molecules to keep it up.

It IS probably just some sort of random effect though.. The leader is
developing, stops as charge accumulates within the leader.  Just then, a
cosmic ray, or something, provides a localized area of lower dielectric
strength, or enhanced field, which provides the direction to start off and
it just keeps going.

There is also a scale issue... the straight segments in lightning are
fairly long (10's of meters)

----------
> From: Tesla list <tesla-at-pupman-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: Parallel and Series LCR Circuit Qs
> Date: Friday, August 11, 2000 6:19 PM
> 
> Original poster: "Antonio Carlos M. de Queiroz" <acmq-at-compuland-dot-com.br> 
> 
> Tesla list wrote:
> > 
> > Original poster: "Jim Lux" <jimlux-at-jpl.nasa.gov>
> 
> > Interestingly, nobody is quite sure why long sparks, lightning, etc.
form
> > forked and erratic channels, unless it is just a random thing and one
> > direction is as good as the other at each step in the leader formation.
 As
> > you can imagine, making measurements about what is going on is, to say
the
> > least, challenging, at those speeds, esp if you don't want to perturb
the
> > fields or phenomena.
> 
> I think that the erratic paths and forking may be caused by dust 
> particles in the air. The spark leaders would try to track along the
> most conductive particles, and the spark would follow the same path.
> It's actually possible see this happen if you try to produce sparks 
> between dusty electrodes. The sparks always hit the most proeminent 
> dust particles, and sometimes it's possible to see a spark tracking
> over a long particle that was blown into the air.
> I wonder what appearance sparks would have in very clean air.
> 
> Antonio Carlos M. de Queiroz
> 
> 
> 
>