From: "JACK L. URETSKY (C)1998; HEP DIVISION, ARGONNE NATIONAL LAB ARGONNE, IL 60439" <JLU@hep.anl.gov>
Date: Mon, 19 Oct 1998 20:36:05 -0500
Hi all-
Dario Moreno writes:
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Dear fellows:
In A.J.P. Vol. 66, No. 6, June 1998, a paper appears by
David Hestenes himself about the Foce Concept Inventory (FCI).
Although the purpose of this paper is not discussing Feynman
as a teacher, the author reminds us that Feynman himself
consider his course a failure except for the best students.
Quickly afterwards, the A.J.P. (Vol. 66, No. 9,
September 1998), M.S. Tiersten and H. Soodak publish a paper
entitled "Propagation of a Feynman error on real and inertial
forces in a rotating system".
What to think of this? It is often said that even
graduated students do not pass the whole of the FCI. It must
be true, since I have seen PhD's failing some elementary
questions. Now the authors of the last paper want us to realize
that even Feynman sometimes got the forces wrong.
I know that Feynman needs no lawyer. After all, just like
Taylor and Wheeler have taught all of us how to teach relativity,
Feynman (Vol. III.) has shown how to beging teaching quantum
mechanics.
Anyway, I think that these papers give our list the
opportunity to comment on some of these issues.
And just to "break the ice", let my begin with three
understatements.
1) I am amazed that still we may find people talking of
"real" forces on contraposition to kinematical forces.
2) From a didactic point of view, the discussion of one
physical situation from two or more points of view,
is something healthy or not? Saying "this happens because
angular momentum is conserved" is the easy way out. I think that
using forces and torques really tests understanding.
3) I would have preferred to be one of Feynman's students,
with all his impromptu methaphors and even mistakes. I do not
want as my teacher someone who WRITES: "in the inertial frame, the
transverse forces arise simply from the inertial tendency associated
with the transverse motion of the weights". ( What does the word
'tendency' mean here? What is the notion of 'weight' doing here?)
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Dario, I think I agree with you, except that I'm not sure
what your point is. If you are saying that the FCI is oversold
as a measure of what physics teaching should be about, then I
have a suspicion that you may be correct.
I have lunch frequently with a former Feynman TA, and he
leaves me with the impression that Feynman detested anything savoring
of pedantry. The further question is, what does all this have with
effective teacching?
Regards,
Jack
"I scored the next great triumph for science myself,
to wit, how the milk gets into the cow. Both of us
had marveled over that mystery a long time. We had
followed the cows around for years - that is, in the
daytime - but had never caught them drinking fluid of
that color."
Mark Twain, Extract from Eve's
Autobiography