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Old January 14th 08, 08:07 PM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 572
Default Standing morphing to travelling waves, and other stupid notions

On Jan 14, 10:53 am, Gene Fuller wrote:
Is your position that
anyone who disagrees with you must be a spoiled brat?


The day you decided that you already know everything there is to know
is the day you started getting more and more ignorant and started
acting like a spoiled brat. Instead of screaming in anger that I am
wrong, I challenge you to produce the math that proves me wrong.

It is
not reasonable to substitute current and voltage for E-field and H-field
when considering the Poynting vector.


Please prove that strange assertion. Is the voltage not proportional
to the E-field? Is the current not proportional to the H-field? For
traveling waves, is not Z0 = V/I and proportional to E/H?

Go take a look at the
actual field configurations for a TEM wave, which includes standing
waves, and report back to us.


That's what I did already, Gene. You should take your own advice. It's
a little harder to visualize than voltage and current but follows
exactly the same concepts plus the right hand rule. Let's take two
equal coherent TEM plane waves forming standing waves in free space as
described by Hecht in "Optics". At one point the forward wave E-field
is at 135 degrees which puts the H-field at -135 degrees. The
reflected wave E-field is at 45 degrees which puts the H-field at -45
degrees.

Efor at 135 deg + Eref at 45 deg = |Efor|+|Eref| at 90 degrees

Hfor at -135 deg + Href at -45 deg = |Hfor|+|Href| at - 90 degrees

For standing waves, the H-field is 180 degrees offset from the E-
field. The power in the standing wave is ExH = E*H*sin(180) = ZERO.
Your assertion that the E-field and H-field are 90 degrees apart for
standing waves is simply FALSE! Please prove fact of physics that for
yourself.

Standing waves do not meet the requirements for an EM wave! Hecht was
right about that.

Feel free to do something besides wave your hands, mount ad hominem
attacks, and engage in obfuscation.
--
73, Cecil, w5dxp.com



c