> Would it not flow through the *best* path versus a lesser
path should
> both options present?
>
> Why would lightning fail to follow a superior path versus
a lesser
> path?
Hi Doc,
Charges gradually distribute themselves in the tree. This
helps establish a potential difference between the tree and
the cloud. Since so little current flows in this process,
the voltage drop is negligible out of the total voltage
difference.
Same thing happens with a tower. Insulate it or ground it,
and all that happens is the charges leak up into the tower.
The tower and cloud wind up with essentially the same
voltage difference...tower grounded or not. Tower connected
to 100 300 ft buried radials and a 100ft deep rod or just
connected to one six foot rod, before the hit it all looks
the about same. I measure less than a few milliamperes
flowing into my 300 ft tower when lightning is in the area.
Even a 1 meg ohm resistor can keep up with the current and
prevent "ticking" across a 1/4 inch spark gap at the base.
Once the strike leader begins resistances can make a
difference, but not before. During the hit a higher
resistance tree would certainly tend to dissipate more
energy in the form of heat, but it doesn't make sense that
resistance by itself would affect the likelihood of a strike
occurring.
Gary's answer sure makes sense to me. I'd like to know some
physical reason why a change in resistance would make the
cloud to tree potential change. That's what doesn't make
sense to me.
73 Tom
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