Energy <=> Money

[Timothy Folkerts <tfolkert@TIGER.FHSU.EDU>]

I think the analogy to money is highly profitable in bridging the gap
between "energy is stuff that flows" to "energy is an abstract property of
a system".  I must admit that a week ago I was leaning much farther to the
"energy is stuff that flows" side than I am now, but I'm seeing that it is
just a bit to simplistic for my tastes.

If I put a $20 bill in the bank today and get a $20 from the ATM tomorrow,
somewhere that $20 is always accounted for.  The same $20 bill doesn't go
from one place to the other.  When I first opened a bank account, I wanted
to think that the bank actually put my dollar bills some box with my name
on it in some big safe, but I quickly realized that this view was not
terribly useful and couldn't adquately explain what I saw happening.

Now with e-commerce, the analogy is even better.  When my pay check is
electronically deposited, there is no way to localize where my money is or
was.  When I use a debit card, there is no money "in" the card, but some
credit is transfered from my account to the retailer's account.  You can't
follow the money from one account and see it cross a boundary, but it used
to be in one place and now it is in another.


Tim Folkerts


> > I repeat:  It is just as easy and far more pedagogically profitable to
say
> > it correctly.  Arguments to the contrary just show an unwillingness to
> > learn physics or how to teach it,  The Great Feynman notwithstanding.
> > Jim Green

> The Great Jim Green not withstanding, most introductory physics students
> (particularly those who will take no other physics beyond that intro
course)
> will not profit from graduate thermodynamic/stat mech/general relativity
> approaches to the topics of energy, heat, etc.  The 'less correct' models
> usually taught and prevalent in intro text books are more easily handled
by
> such students and sufficiently meet the primary goals of these courses.