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Macroscopic work is not energy, it is a process by which mechanical energy
(kinetic, elastic or gravitational) can be either gained or lost by a
system.
It is also the name of a quantity (force times distance) which is
used to know (to measure) how much mechanical energy was lost or gained.
Likewise, heat is not energy. The word heating refers to a macroscopic
process through which thermal energy is either added or removed from a
system.
It is also the name of a quantity (c*m*dT) which is used to know
(to measure) how much thermal energy was lost or gained.
I heard somewhere a statement that "how much heat in a body?" is like
asking how much rain is in the ocean." ...
My brief comment to the opinion that "heat" should be reserved to the
"transmission of energy by the effect of a difference in temperature"
(as stated by Al Bachman).
Emilio, I suspect (withou being sure) that John M. would refer to the
temperature increase of food in the microwave oven as warming rather than
heating. Would the Marsian word gaming be acceptable to you?
4) The First Law is a good guide to this usage: If W+Q=dU and a speaker
wants to maintain consistent usage in a discussion, then just what meaning
should be assigned to each term? Well, there is the Second Law to deal with
as well: if dS=Q/T, then those things assigned to Q should change S.
=name for Q needs to be agreed upon. Usually "Q" is named "heat" -- this is
just fine, but then "heat" is what is done *to* the system -- and in the
process changes the S of the system. ...
5) There should be a sharp distinctions between "Q" and "W"; that
distinction should be that "Q" changes S and "W" does not. Some examples
might help here: a Bunsen burner does "Q", pdV does not, it therefore is
"W". An egg beater *does* give rise to "Q" ie it *does* change S, but there
is no "dT" between the system and the universe. Are we willing to call what
the egg beater does "heat". If we are being consistent with our First Law
and Second Law criteria, we must. If we do not want to be consistent, we
just don't understand thermodynamics and our students will be mightily
confused.