Re: Energy, etc (fwd)

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

I agree with Jim. What about the "magnitude of energy" instead
of "level of energy"?  Yes, to say "the amount of energy" is a
trap promoting the "substance-like" interpretations.

Jim Green wrote:

> > Do we have enough time to go through these steps in teaching
> > elementary physics?
> >
> > Can we allow for misconception of "you cannot subract larger nos. from
> > smaller ones"-type in teaching physics, or do we put in the "imaginary
> > nos."  right away?
>
> These questions mystify me.  There is no simpler way to discuss the concept
> of "energy" than to say it correctly.  _Instructors_ would have to learn
> the correct concepts - and that seems to be almost insurmountable, but
> students have no trouble in learning the correct concepts:  the level of
> energy of a system can be increased or decreased by doing work but energy
> does not "flow".
>
> Would somebody explain to me just why that is so conceptually difficult?
>
> Just use correct language; the students (of any age or stage) will have no
> difficulty what so ever.  Well maybe one would have to explain that  in the
> comics they usually say it incorrectly.