Cecil Moore wrote:
K7ITM wrote:
Of course, it does not require coherent sources to see the effects of
interference.

True, but it does require coherent waves to accomplish
the permanent wave cancellation described at:

micro.magnet.fsu.edu/primer/java/scienceopticsu/interference/waveinteractions/index.html


"... when two waves of equal amplitude and wavelength that are
180-degrees ... out of phase with each other meet, they are not actually
annihilated, ... All of the photon energy present in these waves must
somehow be recovered or redistributed in a new direction, according to
the law of energy conservation ... Instead, upon meeting, the photons
are redistributed to regions that permit constructive interference, so
the effect should be considered as a redistribution of light waves and
photon energy rather than the spontaneous construction or destruction of
light."

This is what happens to the reflected waves at a Z0-match
in a transmission line.

Cecil,

The FSU website you like to reference is a perfect example of the
problem Jim is describing.

As shown, the FSU demonstration is physically impossible. There is no
way for two plane waves to be trucking along independently and then
suddenly decide to interfere.

There is basically nothing wrong with the demo as far as it goes; it
nicely shows the effects of combined phase and amplitude on the
resulting wave. However, the demo is not rigorous science or
mathematics. It is not suitable as an authoritative reference.

73,
Gene
W4SZ