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Re: HEAT1=HEAT2 ?



SECOND REPOSTING (SIX HOURS AFTER THE FIRST). SAME REASON AS THE FIRST.

I corrected myself with this message last nigh. But the message did not
bounce to me and I am reposting it, with an additional comment at the end.
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Who wants to change the ideas? It is only a matter of naming things. The
concept of internal energy, and the idea that it can be changed by one of
two processes, heating and working (dE=Q+W), is well understood. Nobody
wants to change these concepts.
Ludwik
You do! You want to call dE a change in heat.
Leigh

I referred to dE as internal energy. Only Q should be renamed; it should
NOT be called heat, in my opinion. A noun such as thermal pseudo-energy,
for example, may be appropriate to reflect the path-dependence. But you
are correct, Leigh, that my suggestion to retain the name heat for "what
is responsible for T" would mean the renaming of dE and E. So what? We
will return to a synonym "heat" for "internal energy". Why should this
be a taboo? It is only wrong IF the name "heat" is used for Q in the
first law. The traditional "heat is a form of energy" is in line with
heat being a synonym for internal energy. No need for burning our good
old elementary textbooks!

The only "innovation" is a new name for the path dependent quantity, Q,
in thermodynamics. And the name I suggested is not necessarilly the best.
For whose sake should the avoidable mental trap (same name "heat" for two
different quantities) be tolerated?
Ludwik Kowalski

It is our physics. Why only two of us are arguing? Note that my position
and that of Leigh are really very close. Leigh suggests that we should say
"to heat" (a verb) rather than "heat" (a noun). I say invent a new name
and use it both as a noun and as a verb in thermodynamics; this is natural.
Leigh recognizes the common use of the noun "heat" but calls it "vulgar".
I say recognize it as an acceptable synonym for internal energy. It is only
a matter of names, not a matter of concepts. Somebody messed up the
situation (two concepts, one name) and we should correct it.

When I was learning physics heat was first introduced as a "cause for a
change in temperature". It was presented as something inside a body that
can be gained and lost. Its unit, calorie, was defined and we learned how
to use calorimeters. Then we learned about "latent heat" and about
exothermic reactions. Heat was finally identified with internal energy,
but not before we learned the kinetic theory of gasses. Two words for the
same concept (spiral approach) is much better than one word for two
different concepts. What is wrong with this traditional sequence? The
thermodynamists goofed by using the word heat for the path dependent
quantity. Why should elemtary physics vocabulary be changed to compensate
for their mistake? Why should "the recognition from the context" be
necessary in this case?