No Subject

To:      grendel!grendel.objinc-dot-com!tesla-at-uucp-1.csn-dot-net 
Subject: Re: Thunder

%TO            grendel!grendel.objinc-dot-com!tesla-at-uucp-1.csn-dot-net
%FROM          darl
%SYSTEM        tasa1
%SUBJECT       Re: Thunder
%DATE          24/01/96 13:07
%REFERENCE     13734
%ADDRESS       grendel!grendel.objinc-dot-com!tesla-at-uucp-1.csn-dot-net

Subject: Thunder~

 Why are Tesla coils so noisy?  (Especially running in my basement.)  Is it~
the same phenomena as lightning & thunder?~

Ed Sonderman~

   I worked at the physics department of a large university where there was a
pretty good sized Van der Graaf generator.  Sometimes there was a discharge,
especially when the system got so dirty from the debris from the belt that it
cause leakage paths inside the dome.  Although the dome weighed 18-tons and
was made of some kind of iron or steel-like casting, it could be heard for
several hundred feet and sounded like an explosion.  
   My gut feeling is that when a discharge causes depletion of a gas and the
surrounding media collapses with sufficient velocity to cause a series of
pressure variations -- it's the same as lightning and thunder.  These
pressure variations are in the form of a damped wave and it's for this reason
we can hear the resounding clap.  If it were just a single "pop" as the media
collapsed, disregarding that this is mere imagination, it would be so fast
that it would be similar to static.  However the ripples coming from this
pressure variation echos back to the hearer and becomes sound.  Remember the
old cliche:  Where there is no hearer, it's not sound -- just sound waves.~
   Hope this is not too far afield.  It is bordering on Tesla's experiments
with the capacitive effect of the ionosphere and the Earth forming a giant
capacitor where he experimented with world-wide communications and electrical
energy transfer.  In this light, perhaps it is pertinent.....~

Bob Lunsford//~