Re: heat is a form of energy

[Leigh Palmer <palmer@SFU.CA>]

At 9:04 AM -0700 9/9/99, William Beaty wrote:

> On Wed, 8 Sep 1999, Leigh Palmer wrote:
>
> > At 8:49 AM -0700 9/8/99, William Beaty wrote:
> >
> > > ...and Newton's laws are cognitively flawed because they don't incorporate
> > > relativistic concepts.  They have limited application.  We should stop
> > > using them?
> >
> > Explain to me how they are cognitively flawed. I'm unaware of any
> > problem there.
>
> Newtonian mechanics directly implies that there are no "speed limits"
> placed on relative motion, and also that time and mass behave in a
> Classical manner.  Therefor Newtonian mechanics is horribly misleading,
> and we should not teach it.  Instead we should wait until the undergrad
> level, and then teach SR and GR directly, when no "Newtonian" concepts
> intefere, or need to be unlearned.  (Playing devil's advocate here.  In
> reality I think we should teach Newton's laws.  And "heat".  And also the
> Bohr-orbital or "solar system" description of atoms.  And then later
> supply the information that lets students modify and extend these
> concepts.)

I have never encountered the difficulty you see in teaching relativity
after Newtonian physics. I invariably encounter the difficulty with
previously learned energy misconceptions when I teach thermodynamics
students about entropy. Newtonian physics, in my opinion, sets up no
cognitive barriers to a student's progress; reification of energy does
so.

> > > "Heat" works fine as long as we remain extremely aware of its limitations
> > > and of the misconceptions it can breed (no, I myself am not yet totally
> > > aware of these.  I'm still learning thermo and trying to assemble an
> > > intuitive picture of entropy concepts.)
> >
> > By implication you are telling me that "heat" works better than
> > "energy" in some application of the pedagogy. Please give me an
> > example; I can't think of one.
>
> I see that "heat" is the same as "energy", within limits.  Call it
> "thermal vibratory energy" or call it "heat", and we communicate about the
> same concept.  I'm debating Jim Green in this thread at the same time, and
> I suspect that he would strongly object to our replacing the noun "heat"
> with the noun "energy" and therefore claiming that "energy" flows from a
> hot object to a cold one.

You have not addressed the question I ask above.

> > > Touch a warm copper block to a cold one.  "Heat" flows.  The "Heat flow"
> > > concept is a useful mental tool. Do you have an alternative set of
> > > concepts which can be understood by students/teachers in the lower grades?
> > > Or should we remove Thermo from curriculum material below the undergrad
> > > level?
> >
> > If you want to use the analogy why can't you say "energy flows"?
>
> I can!  I thought I was not allowed to say this.   "Energy flow" is being
> attacked too, but apparantly you aren't part of that fight?

If I may be allowed degrees of disagreement then I will say that I
object much less to the use of "energy" than I do to the use of
"heat" in this context. Introduction of a special term implies there
is a difference between "heat energy" and other "kinds" of energy.
I'm sorry, but that is a gross misconception with which many
students entering university are equipped (or hobbled).

> Also, incoming students already understand "heat flow".  If we ban the
> word "heat" and give bad grades if they use it, then the students might
> come to think that "thermal energy" is a different animal as compared to
> "heat", and that two different types of energy exist here.

Do you believe there are different types of energy?

(Didn't I quit this thread before? I shoulda stayed quit!)

Leigh