RE: what good is "percentage error"?

[PHRP@FHSUVM.FHSU.EDU (Roger A. Pruitt)]

> All this comes up as I am writing some exercises for CBL. Today's
> task is a photogate experiment for measuring "g" (and I won't start
> that old thread again by daring to name it!). Now, photogate
> measurements are not my favorites by a lot--but some people like them
> so I'm writing. Anyway, since the regression routines of calculators
> tend not to give you an uncertainty of the fitted quantities, why not
> just do the silly experiment ten times and look at that set of
> numbers? 

This was my thought also when I replied to your original post. In the "old
days" it was hard to make the measurements using the wax paper and the Behr
Freefall apparatus. Nowdays, ten measurements with CBL equipment hardly take
any time.

Students will learn a great deal more about
> experimentation, even at the HS level, and those last nine iterations
> of the experiment are totally painless given technology.
>
> By the way, I think that experiment repetition is a long-ignored but
> powerful benefit of doing experiments with computer or calculator
> data acquisition. Repetition makes the fact that you are making an
> inexact measurement very very clear, and forces one to think about
> how to reduce that collection of results into one answer.
>
> > There was an earlier thread on this topic.
>
> And I probably started it.
>
>
> ==================
> John E. Gastineau                

Roger
==============================================================
Roger A. Pruitt, PhD
Professor of Physics
Fort Hays State University
Hays, KS  67601
==============================================================