Dave wrote:
none of them flow. electrons move, this is called CURRENT. a current
causes a voltage which is related to it by an impedance. that is all you
need to know. power flow, energy flow, birds flying, those are all
secondary effects calculated from the fundamental elements of current,
impedance, and voltage.

Sorry Dave, the essence of an EM wave is its electromagnetic
energy. Voltage and current are the secondary effects of
the photons encountering a conductor. What happens when one
doesn't have a conductor?

What's the voltage and current in the light from Alpha
Centauri? Optical physicists have known for decades what
is the essence of EM waves and they don't use voltage and
current except for some esoteric calculation.
--
73, Cecil http://www.w5dxp.com