Re: conservation of energy

[Jim Green <JMGreen@SISNA.COM>]

> But the -ING needs explaining.  I don't see why the -ING
> forms ought to be emphasized or why they ought to be used
> to the exclusion of the non-ING forms (work, radiation,
> heat, transport and/or flow, et cetera).

John, I agree -- It might not seem like it sometime, but I do agree.

Sometimes it so trivial to say it correctly that it would be remiss not to.
But in a "small" group sometimes shorthand language is helpful to speed
things up.  It would be my position, however, that before beginning the
discussion in class or here and before we use coded language (and maybe
forget that we are not watching Bill Nye the Science Guy) that we make damn
sure that everyone has the same images and understandings for the same
words -- most of the time we do not.

Sometimes precision does not matter -- we may be just spicing up the
language to reduce boredom:   We might say something like When the ball
reaches the wall it thinks that there is a force pushing against
it....  Now only the feeble will think that the ball thinks -- However in
some classes we might be concerned.  But when we say for example that
energy flows likely our students (and maybe ourselves as well) think that
energy really is flowing as does water.

It would be my admonition that, until the student gets to graduate school
and maybe beyond, we be very careful with coded language.

Now a confession: It was long after grad school and I was teaching down the
street from John that I began to sort out T#1. I had asked questions in
grad school but the answers made no sense -- I really shouldn't say this in
public but --- How could "heat" be on the outside of a system (Q) and
"flow" into the system? -- Where was it in the system? -- How is it
different from internal energy?  This was my third time through
thermo.  The instructor had no idea -- - I won't say his name because it
would be recognized.  I worried about this for years while at the IBM
Research Center.  My colleagues there had no explanation. Then I started to
teach and my thermo students asked the same question.  I would do them no
favor if I didn't have an answer.  So....

Most of us teach what we have been taught and those teachers taught what
they had been taught and those teachers taught what they had been
taught....by Aristotle.

But Aristotle was wrong.  Why do we persist?  Why don't we say it
correctly?  It won't hurt.  The students will understand better.  And we
may in fact make sense to each other.  If you can't say it with precision,
you don't understand it.

Jim


Jim Green
mailto:JMGreen@sisna.com
http://users.sisna.com/jmgreen