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Re: Heat through an adiabatic wall?



Without reviving the old thread, let me just summarize some pertinent
implications of the traditional wisdom:

1) Entropy is a state function, ie.; the end states of a system
completely determine its entropy change (delta S).

2) The entropy change of a system is calculable as the integral of dS =
dQ/T over a REVERSIBLE path between the specified end states (or, if
known, by simply evaluating the change in the Entropy state function - eg:
S(T,V,N) for some gas - stated in terms of known state properties.).

3) In this calculation of the system's entropy change, the ACTUAL process
(of interactions with its environment) undergone by a system (and its
environment) is used only to determine the end states of the system under
consideration - as a data input to the calculation (2, above).

4) These considerations are fouled (ie.; fuzzed over and confounded) when
one tries to make some universal isomorphic connections between ACTUAL
processes (and their components) and entropy changes.

Hope this is helpful,
Bob

Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
http://www.velocity.net/~trebor

----- Original Message -----
From: Tim Folkerts <tfolkert@FHSU.EDU>
To: <PHYS-L@lists.nau.edu>
Sent: Thursday, January 06, 2000 11:22 AM
Subject: Heat through an adiabatic wall?


I have been preparing to teach thermo for the first time this spring and
have learned a lot mostly lurking on this list. However, I have come to
a
bit of a paradox having to do with the definitions of heat (Q) and
adiabatic. Let me see if I can state this well.
. . .
Tim Folkerts
Fort Hays State University