Re: The air track experiment

[Bob Sciamanda <trebor@VELOCITY.NET>]

Hi Jack,
Of course I agree that the numerical accuracy of a mathematical model can
never be exactly confirmed by experiment, and that this is important to
convey in our teaching - we should emphasize the error bar that is part of
our knowledge of such parameters as g, including their "constancy".

More broadly, I heartily embrace your admonition to emphasize a particular
assertion of physics as part of a farther reaching model covering a wider
scope of phenomena; not as an isolated (and independently "provable")
fact.  This indeed should be a crucial and re-iterated part of our
teaching.

I guess I'm still curious as to the meaning of your "I think not ..."
which opened this reply to my "Physics differences" post.  Just what is it
that you "think not", and just how were you "bitten three times"?

In a "type (1)" dispute, the court of experiment might well rule that
there is (at least at present) no measurable difference between two
differing mathematical models.  The point is that the verbal dispute
terminates (provoking better experimentation) and does not go on ad
infinitum into unintelligibility (as can happen in type (2) disputes).

Bob

Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
http://www.velocity.net/~trebor

----- Original Message -----
From: JACK L. URETSKY (C)1998; HEP DIVISION, ARGONNE NATIONAL LAB ARGONNE,
IL 60439 <JLU@HEP.ANL.GOV>
To: <PHYS-L@lists.nau.edu>
Sent: Tuesday, August 24, 1999 12:56 PM
Subject: Re: The air track experiment


> Hi Bob-
> . . . Stated another way, the constancy of the acceleration of a falling
> body close to the earth is not a fact determined by any experiment, but
> an idealization that harmonizes the results of many experiments.  A
subtle
> point, but one that I think is worth teaching, because such
idealizations
> are part of the process of physics.
>                                         Regards,
>                                                         Jack