[Phys-L] Re: Energy is primary and fundamental?

[rlamont at POSTOFFICE.PROVIDENCE.EDU (rlamont)]

What is your approach to the following simple problem? A ball is
dropped from rest and falls for 5 seconds. Without using
acceleration, just energy, calculate its speed at the end of the
5 seconds?

Bob at PC

> -----Original Message-----
> From: Forum for Physics Educators [mailto:PHYS-
> L@list1.ucc.nau.edu] On Behalf Of Dan Schroeder
> Sent: Tuesday, August 16, 2005 7:08 PM
> To: PHYS-L@LISTS.NAU.EDU
> Subject: Re: Energy is primary and fundamental?
>
> Apologies for joining this discussion rather late.  I guess I'm
one of
> the "some physicists" mentioned below, although I've never
taught high
> school or even a standard Physics 101 college course.  However,
for
> three years I did teach an honors physical science course, with
energy
> as the unifying concept, for college students who were not
majoring in
> science.
>
> For that course I wrote some text materials which you can
download
> from
> <http://physics.weber.edu/schroeder/energy/>.  Don't get your
hopes
> up--these materials are not even close to being a textbook.
Rather,
> they're a very terse overview of the core physics that students
were
> expected to learn, with a collection of student exercises.  In
the
> course, these materials were supplemented by additional
readings
> from a
> wide variety of other sources, plus hands-on experiments and
other
> activities.  By the way, if you read Chapter 2 you'll see that
I did
> not (nor was it my goal to) eliminate all reference to force
and work.
> However, I did pretty much eliminate acceleration!
>
> Another excellent resource is Bob Romer's old book, Energy:  An
> Introduction to Physics (Freeman, 1976, unfortunately out of
print).
> Without trying to get into an argument with those who feel that
this
> approach to physics is idiotic, here is a list of some of the
> advantages that I see:
>
> * Energy is a familiar concept in everyday life, tangible
because we
> pay for it (in dollars, pounds gained, etc.).
> * Energy is an important political issue that all educated
citizens
> must understand.
> * Energy is a key concept in other sciences:  chemistry,
biology,
> geology, astronomy.
> * Energy-related quantities and calculations provide an
outstanding
> opportunity to develop students' numeracy skills.
> * Energy really is more fundamental than force.  While some
particular
> forms of energy (gravitational, elastic) are closely related to
force
> and are calculated from measured forces, other forms of energy
> (thermal, chemical, electrical) are calculated from entirely
different
> measurements.  Energy in general is a much deeper and broader
> concept
> than force.
>
> Dan S.
>
>
> > Date:    Wed, 10 Aug 2005 12:09:47 -0500
> > From:    Dan Crowe <dcrowe@SOTC.ORG>
> > Subject: Energy is primary and fundamental? (was RE: First
Day
> > Activities or
> >          Demos)
> >
> > John,
> >
> > Some physicists advocate starting a first course in physics
at the
> high
> > school level with energy and energy conservation, but I don't
know
> how
> > to do that.
> >
> > How do you define energy without reference to force or work?
> >
> > How can high school students develop an understanding of
energy
> and
> > energy conservation at the beginning of their first course in
physics?
> > What guidance should a teacher provide in this process?
> >
> > Daniel Crowe
> > Oklahoma School of Science and Mathematics
> > Ardmore Regional Center
> > dcrowe@sotc.org