Thread: Brainteaser
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Old May 26th 06, 04:16 AM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Buck wrote:
Cecil Moore wrote:

But what about the people who say there's no energy in the
reflected wave? Reckon how they sweep all those joules,
whose energy must be conserved, under the rug? :-)


with a jouler's brush?


All kidding aside, whatever number of joules of energy are
required to support the forward power and reflected power
is provided by the source during the transient condition
following power up.

If the source power is 100 watts, the forward power is 200
watts, the reflected power is 100 watts, and the load power
is 100 watts, all the joules per second needed to support
that forward and reflected power was supplied by the source
before steady-state was reached. Anything else would violate
the conservation of energy principle.

This is easily proven using a one second long lossless
transmission line as a conceptual training aid for the
uninitiated.
--
73, Cecil http://www.qsl.net/w5dxp