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Thermodynamics essay debate (for the record)



I forgot to respond to John M's post; My comments are starred and
interleaved with what John M wrote. This is mostly for the record, so if
you are bored with this, delete now!

It appears to me that there may be some talking past each other going on in
the Rauber/Denker exchange.
**I think so.
If I understand it correctly (and I think I do), John D wants to
characterize energy on either "side" of the transfer as either thermal or
mechanical and argues that one can't, therefore, properly characterize the
transfer itself as "Q" or "W" except (possibly) in those cases in which it
starts *and* ends as "thermal energy" or those in which it starts *and* ends
as "mechanical energy."
**I agree
I think it is fair to say that this is at odds with the standard
interpretation of Q and W as characterizing the *mechanism* of the *transfer
itself* rather than the form of the energy before and/or after the transfer.
Furthermore, I think it's not so easy to define "thermal energy" and to
clearly distinguish it from "mechanical energy." Nevertheless, I still agree
with John D's thrust in the sense that it is also tricky to define what one
means by a "thermal transfer of energy" and to carefully distinguish it from
a "mechanical transfer of energy."
**I agree and I agree with the thrust of John D's comments as well!
<snip>
Joel R, on the other hand, seems to be a bit of a fence straddler as hinted
at in his statement:
**My scenario was not intended as a statement of my position on this, my
current position is that I agree with the comments above regarding the
"thrust" of John D's worries over the usual statement of the first law. I
merely wished to indicate a scheme whereby John D's omission of *mechanism*
could never-the-less be accomodated in the 1st law statement for all five
cases that John D mentions in his essay.
This would seem to indicate that, for Joel R, the "transfer" is Q if the
energy *started out* in "thermal form" regardless of how it ended up.
**not for Joel R, but for a self-consistent interpretation that Joel R
offered up as a means of reconciling the omission of *mechanism* ideas and
providing consistancy for the five cases of JD's essay. Joel R thinks its a
lousy scheme for much the same reasons that John D has offered.