Atomic Physics.
What wavelength will pass through - and what will be absorbed.
Short UV and blue can pass. Sneaking through the pickets of electrons
while the Red is absorbed as energy.

Martin

Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder



Jerry Foster wrote:
And, while we're at it, if you pound gold thin enough so that you can see
through it, it's blue...

Jerry

"jim rozen" wrote in message
...

In article , Robert Swinney says...

Chemistry and valence electrons. Gold also. Do a google for

"conductors".

I think he was asking why thermal and electrical conductivity
tend to go hand-in-hand.

The answer is that head is carried by two mechanisms in materials,
by phonons and by conduction electrons. Things that have highly
mobil conduction electrons also conduct heat very well.

Alloys have built-in impurity sites so both the conduction electrons
and the phonons get scattered.

There are some interesting materials like sapphire (see another
thread here) that exhibit no electrical conductivity, but
very, very large thermal conductivity. At some temperatures it approaches
that of copper.

Now someobody has to explain whey copper is red and gold is, well,
gold-colored.

Jim


--
================================================ ==
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
================================================ ==




----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----