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Re: Thermodynamics essay



Various items

a) I would be interested in other peoples opinions, Are JD's 5 cases
incommensurate with usual statement of the 1st law and the usual ideas of W
and Q?? J Mallinkrodt so far has partially offered up an opinion. I'd like
to hear more though.


b) As I mentioned, my quibble wasn't whether or not the 1st law can
accomodate with the usual interpretations; but whether or not the structure
could accomodate the situation at all. I think that JD and JR's opinion has
converged here; to quote JD:

"It is self-consistent in the narrowest possible
sense,"

BTW inorder to be explicit, case (3) from B's point of view is:

Delta E = -10
Q = 0
W = -10

Which appears to be at odds with the conventional usages of Q and W and A's
point of view!

c) I note that JD's five cases actually omit discussion of how the energy is
transferred in *any* of the five processes, it only mentions the forms that
the energy had in the losing and receiving systems, IMO this a priori limits
the application of the usual statement of the 1st law and somewhat begs the
question; unless JD's point is that it is often impossible or at least very
impractical to know how the transfer was achieved. But then one is tempted
to ask about the practicalilty of knowing how the energy of system is
divided into its thermal and non-thermal components as Mallinkrodt pointed
out. Opinions?