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> Why do overhead cables never flap around in the wind?
Actually they do, it's just it's usually very fast and very low amplitude
flapping. Imagine holding out a stretched violin string in the wind, it's
not really going to flap is it?
Anyway, take 200 metres of this stuff (which I make weighs 10 tons):
http://www.csunitec.com/saws/new-river-band-saw.html
pull it *very* tightly between two points (I estimate you're going to need
at least 60 tons of tension in the cable), and then put it in the wind, I
can't see it flapping about too much personally. Some of the really long
cables have dampers on them to get rid of the main resonant frequency, a bit
like what they put on the Millennium Bridge in London to stop it resonating
at the frequency people walked at.
> Come to think of it, why doesn't rain short out power cables?
Because air with rain in it is still an insulator?
> Steelworks. They have furnaces hot enough to melt steel, right? So what
> THE HELL is the furnace itself made of?!
Lots of things have higher melting points than most steels. Ceramics for
instance.
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