Re: The old loop-de-loop

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

1) On Sunday, Nov 16, 2003, John Mallinckrodt wrote:

> It seems to me that a few messages back in this thread,
> Bob Sciamanda supplied perhaps the best phrased answer
> to what I take as your fundamental concern.  To paraphrase Bob:
>
> In its simple attempt to obey Newton's first and second laws, the
> object is continually colliding with the track.  As a result, the
> track and the object deform (as is ALWAYS the case when two
> objects come into "contact") and the deformation is responsible
> (as it ALWAYS is) for the resulting "contact interaction."

I also appreciated that message. The phrase "continually
colliding" is highly useful and easy to accept. It does not
call for a radical departure from what is in our textbooks.

2) On Friday, Nov 14, 2003, John S. Denker wrote:

. . . Yeah.  Teaching is full of dilemmas. . . .

> . . . Progress necessitates doing some things
> differently from our predecessors.  Let's figure
> out what is the right thing and do it.

True. But promoting radically new approaches, (for
example, "do not use the concept of force, or "do not
think in terms of the cause-and-effect") without being
sure that teachers are well trained in new approaches,
can do (and often does) more harm than good. That
is one of the dilemmas.

3) Thanks to all who contributed to this interesting thread.
Ludwik Kowalski