Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: Energy as ability to do work

>> I vote for "just plain wrong".
>
>Now to me this sounds more like "lacks generality", since it's just
an
>example of a case where the "ability to do work" point of view does
not
>apply (and is not usually even attempted).

Now we really do have a divergence on what the meaing of "is" is.

When I see something that is meant to be an analogy or an example
that
lacks generality, then I say that it lacks generality and that's the
end of it.

OTOH when I see something that purports to be a definition and
purports to
have vastly more generality that it really does, I say it's just
plain wrong.

If you want to "define" a sub-type of energy that isn't general
enough to
include thermodynamics, then it would be a big help to warn people
of the
limitations.

______________________________________________________________
copyright (C) 1999 John S. Denker jsd@monmouth.com

Yes, I agree that "defining" energy in general as "ability to do work (.)"
is just plain wrong. When I said I've been drifting back toward this point
of view, I didn't have definition in mind, but just a possibly useful way of
helping students visualize the significance of this rather abstract "state
variable" in a more concrete way, only in the case of a few ideally
reversible processes such as the compressing and stretching of a spring and
the raising and lowering of a suspended object.

Fred
______________________________________________________
Fred Lemmerhirt
flemmerhirt@mail.wcc.cc.il.us
http://chat.wcc.cc.il.us/~flemmerh/physics.html
Waubonsee Community College Sugar Grove, Illinois

-----Original Message-----
From: John Denker [SMTP:jsd@MONMOUTH.COM]
Sent: Tuesday, October 26, 1999 12:51 PM
To: PHYS-L@lists.nau.edu
Subject: Re: Energy as ability to do work

At 11:12 AM 10/26/99 -0500, Lemmerhirt, Fred wrote: