Re: Thermodynamics of springs

[Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>]

Referring to this:

>  >That is why I think that Socrates had no right to ask the
>  >fictitious H.S.S. character for a numerical comparison
>  >between the potential energy stored in a chemical compound
>  >and in a compressed spring. It was not a fair question.
>  >Seeing the analogy was already a big accomplishment.

John Denker wrote:

> ... But once the analogy has been seen, the numerical part of the
> comparison is so easy that there's nothing to lose by asking for it...

True for a one-to-one dialog, as it is in this game. But in general
attempts to put too much into the first physics course are not
desirable, in my opinion. It takes time to start thinking in terms
of physics. I do believe that "less can be more". Let them enjoy
illusions of mastery instead of frustrations produced by "so much
of it". Yes, there is a lot to lose by trying to put too much on little
shoulders.

Perhaps real high school teachers will share some ideas on the
subject of "less is more". I was teaching high school physics for
only two years. This was 30 years ago and it was not a typical
school.

Let me respond to Leigh at the same time. I was not claiming that
the L=Lo*(1+alpha*dT) can not be presented as a state equation
to those who know what a state equation is, and how to use it.

> ... we simply observe that, in  the first approximation,
> L=Lo*(1+alpha*dT). We do not say that this is a state equation.