Re: Carbon Plasma? (was beanstalks)

From: Earl Colby Pottinger (earlcp_at_idirect.com)
Date: 06/14/04 

Date: Sun, 13 Jun 2004 20:34:25 -0500

mmeron@cars3.uchicago.edu :

> In article <40cc405a$0$3021$61fed72c@news.rcn.com>, jmfbahciv@aol.com
> writes:
> >In article <cahe9p$8jn$1@gw.retro.com>,
> > gherbert@gw.retro.com (George William Herbert) wrote:
> >>Gordon Couger <gcouger@NOSPAMprovalue.net> wrote:
> >>>"Henry Spencer" <henry@spsystems.net> wrote:
> >>>> Gordon Couger <gcouger@NOSPAMprovalue.net> wrote:
> >>>> >When the current discharges down the cable it vaporizes and forms
> >>>> >plasma and
> >>>> >becomes even a better conductor for the rest of the current. Not only
> >>>> >destroying you beanstalk but producing an EM pulse that will kill
most
> >>>> >electrical equipment in several 100 square miles.

> >>>> Hard to imagine how we could ever have developed electricity, with
> >>>> every

> >>>Proper grounding does wondrous things.

> >>I think you missed the point. If electrical discharges of that
> >>nature and magnitude cause damaging EMP, then we'd have lost all our
> >>electrical grids and equipment repeatedly, every summer day in
> >>some parts of the nation.

> >But that happens!

> No, it doesn't. I haven't seen *all* the electrical grid and
> equaipment being lost *repeatedly*, *every* summer day, in any place.

> Always read carefully what you respond to.

Nor in the case where present day existing carbon fiber structures are hit by
lighting I have never heard of the structures turning to plasma or in most
cases even catching fire. The fact is it takes a lot of energy to convert
solid carbon in any of it's forms to a conducting plasma.

To make matters worse for this claim of carbon structures conducting electric
current, in a good composite material there is minium contact of the fibers
to each other as the goal is to imbed each fiber as completely in the matrix
material possible to max transfer of tension between fibers. Fiber to Fiber
contact does not transfer tension. Because of this only a small percentage
fibers form a conducting path there is a lot of resistance to conducting a
current,

Now a question to something I really know nothing about, there have been
references to bucky tubes being ballistic conductors and these have only one
value resistance regardless thier length. However in the case of beanstalks
no-one plans to build bucky tubes the full length of the stalk infact it
likely that tubes a few meters in lenght will the maxium length ever needed
or used. So if separate ballistic conductors conduct in series does the
resistance add up or does it stay the same as a single conducting fiber.

                 Earl Colby Pottinger 

-- 
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Relevant Pages

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