I think that the reason is simply to increase the distance that the
electricity must travel over the surface of the conductor. Out and around
inside then back out... etc etc etc. After all, even when wet, the
resistance of this path far exceeds the resistance of the transmission
line. Which, I must add, is impedance matched at both ends to optimize
transmission efficiency.
And, as it has been stated before, if it did start to conduct, the heat
would evaporate the water. But this doesn't help during a rainstorm.
I also don't think they are shaped that way to keep part of it dry. These
things are designed for all types of climates and weather conditions. It
would be a pipe dream to think you would be able to keep something like
this dry in some spots during a rainstorm.
Question: Someone stated that high voltage passed through water more
easily. I'm not familiar with this. I have always been told that the
conductivity depended on the purity of the water, regardless of the
voltage applied. Remember that this is AC, not DC from a Van de Graff
generator. Remember, water does have an impedance when AC is applied
instead of being polarized by a DC voltage. Any thoughts?
--
James Bradford Shue jshue@comp.uark.edu
University of Arkansas Voice phone:(501) 575-6059
Physics Lab/Demo Curator FAX Number: (501) 575-4580
WWW Page http://comp.uark.edu/~jshue