Re: heat, a nonconserved quantity

[John Denker <jsd@MONMOUTH.COM>]

At 04:33 PM 1/31/01 -0700, Larry Woolf wrote:

> If heat is a conserved quantity, define heat and the conservation law that
> it obeys.

Heat is not a conserved quantity.  That's been known for well over a
hundred years.
  http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Clausius.html

By way of analogy:  snow is not a conserved quantity, either.  Yet I'm
reasonably certain that snow exists.  Talking about snow has considerable
pedagogical and practical utility.  The word "snow" is a noun (as well as a
verb).


> Bohren's point is that almost all situations can be better
> described by using temperature instead of heat.  Temperature is well
> defined.  Heat is not.

Some people from time to time say stupid things about heat.  But then
again, people have been known to say stupid things about snow, and about
energy and momentum and silicon and hundreds of other things that somehow
continue to exist.  Just because some people say stupid things about them
doesn't prevent the rest of us from properly using these nouns and
benefiting from the ideas they represent.