Re: batteries (again)

["John S. Denker" <jsd@MONMOUTH.COM>]

Justin Parke wrote:
> Does an electric field always exist between the terminals of a battery?

Yes.

(This excludes dead batteries and other pathological cases).

> When a conductor is placed in contact with the terminals of a
> battery, is the electric field constrained to exist only within
> the conductor?

No.  Why would anyone think so?

(This excludes perfect conductors [which would completely short
out the battery] and other pathological cases.)

(If you hook a perfect conductor to a perfect battery,
it's an impossibility.  If you hook a near-perfect conductor
to a near-perfect battery, it will explode.)

> If there is an electric field that exists outside the conductor
> near the terminals of a battery, is there a flow of charge (say
> ions in the air) in that region, and if so, is it measurable?

Yes and yes.
Electrical measurement technology is very, very advanced.
Any halfway-reasonable thing you can think of can be
measured.  It might be expensive, though.