OK, I'm a little confused. Well, maybe more than a little.

Starting with energy as the "ability to do work" and power as the rate
at which energy is "transformed" into work, things quickly get muddy.

Energy passing through an imaginary surface (or point or plane) would
not actually do any work in passing through, and in fact would retain
its full potential to do work after having passed through.

What then is power density? Is it the amount of work that the energy
passing through a unit area of the surface "could have done" had it been
actually and fully "captured" at that surface? There is no real power at
that surface, is there?

While power (and work) absolutely require energy, it strikes me as
metaphysical whether all energy ultimately does do work and produce
power. I don't think physics requires that, and it seems that lot of
radiated energy is not obviously being transformed into work. So is
energy without power really impossible, Cecil?

Been away from this for a longer bit than I'm comfortable mentioning.

Chuck. NT3G

Cecil Moore wrote:
chuck wrote:

Technically, is it not energy that leaves the transmitter and is
received by the receiver?


Technically, RF energy passing a point/plane during a unit
of time is RF power (joules/sec). We can't have one without
the other.