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[Phys-l] book/movie review: The Mechanical Universe

I recommend most folks should by a copy of
_The Mechanical Universe_ (both volumes). The
first volume is subtitled "Mechanics and Heat"
The treatment of mechanics is exceptionally clear.
It has a nice "flow" to it, as it moves toward
the goal of solving the Kepler problem. The
Kepler problem will never be easy, but they lay
the groundwork so that ordinary mortals can get
through it.

If/when you think lecturing is appropriate, you
could provide pretty decent lectures in mechanics
just by showing the "Mechanical Universe" movies.
You can earn your pay by pausing the movie to
answer questions when they come up ... and
by turning it off before it gets to the "heat"
part of "mechanics and heat".

In the chapter that introduces "heat", they
repeatedly equate thermal energy with the
random "kinetic" energy of the molecules. It
makes me want to tear my hair out. I *know*
Goodstein knows better than that. The fact is,
in an ordinary solid, half of the heat capacity
is associated with kinetic energy, while the
other half is associated with potential energy.
Why do so many textbooks get this wrong?????

Also the chapter on entropy makes me want to
tear my hair out.
dQ ???
If I never see another dQ it will be too soon.
There is no state function Q such that dQ = T dS.

For details on why not, see

Entropy is defined in terms of probability. Period.
Entropy is not defined in terms of energy or vice versa.
Entropy is well defined even in situations where the
temperature is unknown, undefinable, irrelevant, or zero.