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Old July 11th 03, 05:45 PM
W5DXP
 
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Jim Kelley wrote:

"W5DXP" wrote in message
Yes, it does, which is not at all if we already know the
reflected irradiance which is a given.


Obviously, the load determines the boundary conditions and so it is not
irrelevant. You said that it was, and that's not correct. The load
impedance is what determines the reflectivity. Go ahead and disagree.


I probably should have used the word "redundant" instead of "irrelevant".
If the reflected power (irradiance) in a Z0-matched system is a given,
then the value of the load is redundant information and is NOT needed
for a solution.


:-) Yes, very technical. If a math question was posed, I must have
missed it.



What is the superposed sum of the
two above waves?



Zero.


What happens to the intrinsic energy pre-
existing in those waves before they cancel each other?



The answer the intrinsic energy in the waves where the waves exist is stored
in the transmission line, and nothing happens to energy where waves don't
exist. The waves in question don't convey energy from the source to the
load - obviously because they don't propagate from the source to the load.
It ain't rocket science - as you're so fond of saying.


Using the values above, calculate the rate of flow of energy equal to
V*I. That's how much energy is involved in your dilema here.



The rate of flow of energy has to be 100 joules/sec since the energy
in those two waves cannot stand still and cannot be destroyed.



The rate of flow of energy "in" those two waves is not 100 Joules per
second.


We
already know that the energy in those two waves joins the forward-
traveling power wave toward the load.



The energy does travel forward, but not by way of those two waves.

73, Jim AC6XG