Re: definition of "electrostatic"

[William Beaty <billb@eskimo.com>]

On Mon, 5 Oct 1998, Bob Sciamanda wrote:

> Hi Bill!
> I see your purpose!  I would still restrict the word "static" to mean
> independent of time, not just a snapshot of a time dependent phenomenon.
> We can save the day by observing that the DC current situation is a
> hybrid combination:

Yes.  I realize that in part I am trying to cure yet another problem: 
many of us commonly use "electrostatic field" interchangably with
"electric field."  We also commonly swap "electric force" and
"electrostatic force."  Also "electrostatic charge" and "charge" are
usually perceived as meaning the same thing.  If this did not happen,
if we all treated "electrostatic field" as very different from "electric
field", then I'd have less to complain about.  But since "charge" is
often described as "electrostatic charge", there is a tendency (at least
for many beginners) to imagine that the charge distributions (the "static
electricity") must all go away as soon as electric current or varying
potentials arise.  It makes a sort of sense... if "current electricity" is
in a flashlight circuit, then there can be no "static electricity".  Yet
in reality, the "static charge" in a flashlight circuit is flowing.

> Once the turn-on transient period is over, a static (unchanging) charge
> distribution has been built up (and will be maintained) on wire surfaces
> (and anywhere there is a spatial change in conductivity).  This static
> charge makes the electrostatic field which drives the current.  The
> charge distribution and the fields are static; the charge carriers are
> moving  -  some call the entire situation a quasi-static situation.

And this applies to an AC system too (at least when the circuit is far
smaller than the wavelength, and if we ignore the transformer.)   So
when dealing with AC appliances, must we say that the electroSTATIC charge
is extremely non-static?  :)  Certainly, if we define "electrostatics" as
meaning "the section of science which deals with charge distributions and
e-fields."

Another point: the same issues SHOULD arise with magnetostatics.  There
SHOULD be confusion about "magnetostatic force" versus "magnetic force". 
Yet there is not, and K-6 people rarely encounter "magnetostatics", yet
they have the "static electricity" concept pounded into their minds by the
Electricity chapters of their texts.  I suspect that this is caused by a
lack of a particular word... what is the electrical analog to the word
"magnetism?"  "ELECTRICISM?"  We can easily discuss magnetism and magnetic
fields, but the dual, the electricism and electric fields instead are
warped into an explanation of "Electricity which does not move."  Too bad
the term "static" cannot be entirely removed from K-6 texts, and with it
many of the "unmoving electricity" conceptual problems.  And at the same
time that kids are pouring iron-filings onto magnets, they could also be
pouring dry grass seed onto charged rubber rods to see the e-field
pattern.  Yet the latter seemingly has nothing to do with the usual K-6
goal of teaching about the two kinds of electricity: current electricity
and static electricity.

Fortunately monopoles don't exist, and the public isn't plagued with an
erroneous belief in a "form of energy" called "current magnetism".  Or
should that be "current magneticity"?     ;) 

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