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Re: ENERGY WITH Q



Ludwik Kowalski wrote:

Consider the First Law formula, dU=X+Y, where X and Y are
two familiar boundary indicators. To avoid pseudo-arguments I
am NOT going to call them heat and work. The corresponding
Martian words, "qunergy" and "wunergy", are less confusing.
Here is my two questions:

1) A cold plate located below a glowing infrared source is
declared to be a thermodynamic system. The U of the system
is increasing because its temperature is not as high as the
temperature of the source. Transfer of energy does take place
from the source to the system. Should this process be called
qunergy or wunergy? According to most textbooks it is
qunergy because it is dues to a difference of temperatures.
The familiar terminology is "transfer of energy by radiation."
Is this the X process or the Y process?

2) I suppose that most of us no longer consider X and Y to
be "forms of energy." The dU is a change in energy but X
and Y are something else. That is why I am referring to X
or Y as a "boundary indicator." Is this term acceptable?

I don't understand the question.
I don't see any questions, except trivial questions, here.

Consider the analogy to a relay race. The baton is a
conserved quantity, in analogy to energy which is a
conserved quantity. The process of transferring the baton
is not "the" baton.
-- You can describe the transfer without saying much about
the baton.
-- OTOH if you are describing the baton, one of its most
interesting properties is its conservation, which has to
do with limitations on how it can and cannot be transferred,
so when you describe the baton you usually want to say
something about transfers.
-- Saying that in such-and-such situation there is no
transfer is not at all the same as saying there is no baton.

Isn't this obvious? What's the question????

If the question is whether writing dU in terms of energy
transfer is acceptable, the answer is no, for reasons
having nothing to do with language (Martian or otherwise).
The reasons are not particularly clearly manifested by
the radiative heating example, but are manifested in many
other ways, as discussed in:
http://www.monmouth.com/~jsd/physics/thermo-laws.htm#sec-eschew-w+q