Re: Cause and Effect

[Leigh Palmer <palmer@SFU.CA>]

> On Tue, 24 Oct 2000, Leigh Palmer wrote:
>
> >  >This is a misconception, after all.  It is not correct.  However, a large
> >  >number of our students think this way.  At least it seems to me (does the
> >  >physics education research have anything to say on this?).
> >  >
> >  >I am just wondering if we may be inadvertently reinforcing this
> >  >misconception.  Maybe I should use a different header?
> >
> >  I understand the problem; I just see no reason one should not simply
> >  tell students that a cause need not precede an effect, but it *may*
> >  do so. An effect cannot precede a cause.
>
> I'm glad you agree with me that instructors need to explicitly mention
> this when using the word "cause".  Granted, you may have, Leigh, but
> before this thread, I never thought to do so (assuming it was a given that
> students would properly interpret the equationa and know that force
> doesn't precede the acceleration). Was I alone?  How many of us actually
> told students that a cause need not precede an effect?

That is certainly made explicit the first time relativity is taught,
at least by me. I can't recall ever noticing a misconception of the
sort you suggest among my first year students. They seem to be able
to cope with F = ma satisfactorily. The only problem I encounter is
that many of them who know how to do the problems don't seem to
believe that F = ma works in the real world. That is a much deeper
problem.

Leigh