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Recently the following passage came to my attention:
In the section entitled "HEAT IS /NOT/ A FUNCTION OF STATE" it says:
«You can strengthen your insight into these concepts by now returning to
the discussion of impulse and change of momentum in Section 1.9. Notice
that impulse, like quantity of heat transferred, is path dependent. In order
to calculate an impulse, we must know how the force delivering the impulse
varied instant by instant (i.e., we must know the "path" of the force with
respect to the succession of clock readings). If we have this information, we can
evaluate the impulse as an integral (i.e., an area under a graph). The situation
with respect to transfer of heat is exactly analogous: Delivery of impulse
(which is /not/ a state variable) results in a change in the state variable called
"momentum." Transfer of heat (which is /not/ a state variable) at constant
pressure results in a change of the state variable temperature.»
Would anybody care to comment on this? Would you say it is:
-- About typical of how the topic is presented nowadays.??
-- Different from the typical presentation, but not much better or
worse, just different. Possibly useful as a sidelight, as another
way of looking at things.??
-- A significant improvement over the typical way of explaining
these points.??
-- Abjectly wrong in almost every detail; a poster child for wrong
physics and bad pedagogy.??
-- Or ?????
Extra-credit question: What do you call the legume that grows across
the top of the doorway?
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