Re: lightning rod question

From: Steve Harris sbharris_at_ROMAN9.netcom.com (sbharris_at_ix.netcom.com)
Date: 10/24/04 

Date: 24 Oct 2004 12:15:31 -0700

spamspamspam3@netzero.com (Edward Green) wrote in message news:<eca320d0.0410240616.72e8e767@posting.google.com>...
> timothy42b@aol.com (TimR) wrote in message news:<87af0be7.0410240256.5ea16ad6@posting.google.com>...
>
> > Back in engineering school one of the professors was famous for
> > studying lightning. I recall him saying #10 wire was perfectly
> > adequate, that we had to remember the wave form. A lightning stoke is
> > a damped sinusoid, it is not like trying to pass 30,000 Amperes DC
> > through a wire.
>
> That comment doesn't make much sense to me. What's waveform got to do
> with it? What matters is power dissipation.
>
> Or I guess that's what you are suggesting: the pulse is short enough
> that much higher instantaneous powers can be tolerated than at steady
> state. Why didn't you just come out and say that!? ;-)

COMMENT:

Yes. The waveform is "damped sinusoid." In this case it's the first
descriptive word that's important, not the second <g>.

SBH

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