From: KPJ (kpj@sics.se)
Date: Mon Dec 06 1999 - 06:34:48 MST
It appears as if the EvMick unit <EvMick@aol.com> wrote:
|And does vacumn have a tempeture? Is the "fridgid depths of space' real or a
|bogus holiwood meme?
The ``Light and Matter'' <URL:http://www.lightandmatter.com/area1book2.html>
text book defines temperature as ``any form of energy that can be conducted
between objects in contact, without any force'', or, informally, as ``total
kinetic energy of random motion of all atoms in an object''.
One can view a vacuum as an extreme thin gas :-) and in a partial vacuum,
the particles can move around with extreme speed, and the temperature can
therefore become vert high, indeed.
A quantum mechanical definition could take zero-point energy into the
discussion. My current physics database does not include quantum mechanics,
so I cannot help you out on that one.
|What is the tempeture of a vacumn? how come it keeps my coffee hot in the
|thermos?
_Empty_ space has no temperature. [See note above on quantum mech, though.]
Your Thermos(tm) contains a partial vacuum between mirroring surfaces.
The heat can move from A to B by: radiation, moving atoms around, and/or
by conduction of heat between atoms. The mirrors stops the radiation bit,
there exists no atoms to conduct the heat (except at the neck of the flask
where the manufacturer used a substance which does not conduct heat very
well), and the vacuum has only a few atoms to move the heat between the walls.
The heat leaks out using conduction and radiation, but stays put long enough.
You wouldn't complain if your hot drink had cooled after a week, would you?
|Would sweat in a vacumn cool you?
With or without a space suit on? !-)
a. [With]: Depends on your cooling system. If it works properly, it should
take care of your sweat, which should cool you down.
b. [Without]: Yes. And the part of in the shadow from any local star would
radiate away much heat, until you blow into pieces by the the boiling of
your water contents by the dropping pressure.
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