Keith Dysart wrote:
You need to read more carefully. I made no statement about
the energy incident upon port 2, only about the energy
flowing into port 2, which, after the 18 W generator is
turned on, is
Pcp2(t) = 32 + 68cos(wt)

If we have two pipes each carrying one gallon of water
per minute in opposite directions, we can agree that
the net flow of water is zero. But you are taking it
one step farther and arguing there is no water flowing
at all which is a ridiculous assertion. I'm going to
ignore this latest obvious diversion.
--
73, Cecil http://www.w5dxp.com