Cecil Moore wrote:

Jim Kelley wrote:

The momentum in reflected waves changes direction upon reflection.
What part of that do you need to have explained?


What causes 100% reflection when the power reflection
coefficient (reflectance) is only 0.5?

If you would just work the problem the hard way, you would see where
you're misconception lies. Any given wave front will never reflect
100% from a surface which is only 50% reflective, no matter how
vicious your insults become, how may URLs you cut and paste, or how
furiously you wave your hands. But when you work the problem as has
been suggested you will see how energy gets from source to load. It
does not rely on macroscopic layman's explanations or mathematical
shortcuts in order to get there.

The only energy "lost" by partial reflection in the process is that
which is reflected back toward the source or stored in the system
during the transient period. The sum of all the partial reflections
equals the energy stored in the system (less the portion of energy
admitted to the load or reflected back to the source). After the
transient period, no energy is reflected back to the source, and the
energy entering the system from the source equals the energy existed
the system through the load.

I know that you understand the difference between potential and
kinetic energy in mechanics. Please try to consider that the concepts
are no less valid in electromagnetism. (Note that we even use the
word 'potential' to describe voltage.)

73, ac6xg