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Re: Capacitor charge, were is it?
"Now what would happen if we cut that rod in two, put a very tiny
microammeter between the two half-rods and connected the leads of
the microammeter to the two half-rods such that the ammeter was now
in series with the rods, and then we turned on the field V. We
agree that in the steady state there is no current flow in the rod.
But what would the meter read if we started with the field off and
the we turned it on? Would the meter ever read any current? Would
the current start and flow in one direction and stop, or would the
current turn around and flow back the other way? Would there be
any net charge transferred through the microammeter if we left the
voltage on?"
At the time the field was applied there would be a
transient current through the microammeter, since the two
ends of the rod to which it is connect are, in effect, small
capacitors coupled to the two plates. After the initial transient
those two capacitors are charged, so a net current had to flow.
On turnoff the same thing will happen, with the direction
of current flow reversed.
(Above assumes that that I read your statement right and
this is not a trick question which fooled me! I'm all pooed
out tonight.
Ed