>> There is no such thing as "no voltage difference" when you are talking
I agree a "no difference" situation id highly unlikrly, but I agree with Jim
in you are unlikely to see any where near a million amps. 50,000 to 100,000
for the really big monsters, or the so called "super strikes"
>> a million amps or so.
> Doubt you're going to see a million amps. really, really big strokes
> might be 100kA, but that's in the stroke, not in some grounding wire
Even if it does hit that it's a very short duration peak (probably no more
than 10 miliseconds or so) with rapid rise and fall times. So the power
disipated is considerably less than is usually expected.
> (the tower might carry that, but as soon as you start dividing the
> current up among various paths to "earth" the current in any one
> conductor gets smaller). The peak current can also decrease because of
> the inductance of the conductors spreading the pulse out.
> Most lightning is in the 10-20 kA range. The long duration continuing
> current that starts fires is actually in the hundreds of amps range.
> 100kA strokes are rare.
Probably less than a half percent and they tend to ocurr in the cooler
weater. Also they are *apparently* associated with the "Sprites" reported by
> See, e.g. M. Uman, "Lightning" or anything by Uman and Rakov in the last
> 10 years.
Iman is good, but you might find some NASA with some additional information
on the super strikes.
> A lot of "lightning damage" is from induced currents, rather than direct
> conduction. That several kiloamps with a few microsecond rise time
> flowing through the lightning down conductor has a pretty hefty magnetic
> field, and if you have a loop with a couple square meter area that
> intercepts that field connected to a sensitive circuit, it fries. Folks
> fooling with small Marx banks, medium sized Tesla coils, and medium
> hobby Van deGraaff generators find this out real fast. The energy in
> the "bang" is low in all these (a few joules), but they are notorious
> electronics killers at short range (garage door openers are a common
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