Xref: utzoo sci.electronics:20681 sci.energy:5145
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!wuarchive!uunet!comp.vuw.ac.nz!waikato.ac.nz!canterbury!elec140
Newsgroups: sci.electronics,sci.energy
Subject: Re: Gold saves energy.
Message-ID: <1991Jun6.161303.972@csc.canterbury.ac.nz>
From: elec140@csc.canterbury.ac.nz
Date: 6 Jun 91 16:13:03 +1200
References: <1991Jun5.163512.1314@zoo.toronto.edu> <1987@ole.UUCP>
Organization: University of Canterbury, Christchurch, New Zealand
Lines: 35

In article <1987@ole.UUCP>, ssave@ole.UUCP (Shailendra Save) writes:
>    There is something known as the skin effect, due to which, the
>    higher the frequence, the closer to the skin the current travels.
>    This is one of the reasons why the cables are never solid, but a
>    bundle of thinner wires. The other reason is of course to have some
>    tensile strength.
>    With this knowledge, I would think that the bulk would not matter
>    so much as the "skins" of the individual wires. So we would have to
>    just coat the outermost wires with gold(so that they don't corrode)
>    but coat all the inner wires with silver (since they are not in
>    contact with external factors) so as to reduce resistivity to
>    current through it.
>
>    Just my 2.76 yen worth (today's rate).
>
>    Someone please verify the skin effect stuff.

What you say is correct as far as it goes. However the "skin depth" (ie the
thickness of the "skin" carrying most of the current) is dependent on
frequency. The higher the frequency the thiner the "skin" and you've got
problems. However from memory, the skin depth at 50 Hz (yes I'm in that part of
the world) is about 10 mm, which equates to a lot of gold !-)

*********************************************************
Chris Kaiser
Postgrad - Elec Eng Dept
Canterbury University
Christchurch, NEW ZEALAND

E.MAIL: kaiser@elec.canterbury.ac.nz
*********************************************************
	"When you're fresh out of lawyers
 	 You don't know how good it's gonna feel"
		- Al Stewart, 1988
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