Mike Monett wrote:
Roy Lewallen wrote:
[...]
The traces are drawn in the order Eh, Ee, and total. During the
initial forward wave, Eh and Ee are equal, so the Ee overwrites
the Eh trace.
Good - thanks.
[...]
My problem here is someone wrote a web page that claims the
electric and magnetic fields are orthogonal:
http://www.play-hookey.com/optics/tr...etic_wave.html
You're making the same error that Cecil often does, confusing time
phase with directional vector orientation. The orthogonality of E
and H fields refers to the field orientations of traveling plane
TEM waves in lossless 3D space or a lossless transmission line, at
the same point and time.
Now you are confusing me with Cecil. I have no difficulty with the E
and H field orientation.
The E and H fields of these traveling waves are always in time
phase, not in quadrature.
Yes, that's what I tried to explain to him also.
The graphs show the magnitudes of the waves at various points
along the line. These represent neither the time phase nor the
spatial orientation of the E and H fields.
I tried sending him an email to show if the fields were
orthogonal as he claims, it would look like a pure reactance, and
no energy would be transmitted. But he is stuck on his idea and
won't budge.
Good for him - he's absolutely correct.
There is a bad mixup here. He claims:
"Note especially that the electric and magnetic fields are not in
phase with each other, but are rather 90 degrees out of phase. Most
books portray these two components of the total wave as being in
phase with each other, but I find myself disagreeing with that
interpretation, based on three fundamental laws of physics"
He claims the E and H fields are in quadrature. I claim he is wrong.
And you're right. I apologize. "Orthogonal" usually refers to spatial
orientation, so when you said that he said they're orthogonal, my
reaction was that it's correct. But I didn't look at the web page. I see
by looking at it that he also says the two are in time quadrature, which
of course is incorrect as you say. His "fundamental laws of physics" are
certainly different from everyone else's. Thanks for providing a good
example of the pitfalls of relying on the web for information.
Again my apology. You do indeed have it right. Incidentally, it's not
possible for a medium to have a purely reactive (imaginary) Z0 at any
non-zero frequency.
Roy Lewallen, W7EL