Thread: conduction
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Brian Gaff \(Sofa\) Brian Gaff \(Sofa\) is offline
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Default conduction

Because you are inquisitive. There is of course an electrostatic field
around a conductor and the air is not really a great insulator and can break
down and the two different potentials want to be connected. I see no real
quandary. However Superconductors are a different thing altogether. They
somehow can join together in such a way that resistance is just not there at
all, so unless you take energy ot of a system by magnetic loads etc, if you
connect the wire into a loop current will flow all the time until the
leakage reduces the voltage. However its not terribly efficient as the
power to keep it cold enough is quite great. I do not see how you can have
a superconductor at much above absolute zero, ie the temperature where any
attempt to cool it cannot happen as there is nothing colder. I'd imagine
that the Brownian motion in materials at room temperatures is where
resistance comes from, since otherwise you would not get noise in valves and


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"williamwright" wrote in message
If two conductors are merely touched together electricity can flow between
them. That just seems too easy somehow. I mean, just touching? That's
ridiculous. I've always thought that it ought to need more intimate
bonding between conductors for current to flow. Even if the conductors
aren't touching, sometimes there's a spark.

Another question. Why do I wonder about such things?