Cecil Moore wrote:
Jim Kelley wrote:
Convention dictates that current
alternates in direction, and that standing waves don't. They stand.
Heh, heh, the seduction by the math model is worse than I thought.
It's not so much a matter of being better or worse than you thought.
It's just different than what you think.
You don't really believe that standing waves don't alternate
in direction, do you?
I don't think anyone believes that standing waves alternate in
direction. Most people know that standing waves are stationary, and
that alternating current flows in alternating directions. But the two
things are not one in the same. You need to think more carefully about
what a standing wave is.
Sorry for the dangling prep.
The standing wave current changes phase by 180 degrees every
half cycle.
At a given point is space alternating current changes phase
continuously. But standing waves don't change position, and don't have
a direction, let alone a *CHANGE* in direction. The current plot on
your web page shows a standing wave plot of alterating current magnitude
as a function of position. The phase at each position changes
continuously with time.
Listen carefully. The plot indicates the magnitude (and potentially a
phase) of an alternating current as a function of position. The phase
at each position changes continuously with time. It's RF AC, but it's
not a traveling wave plot.
It's not a matter of current flow into or current flow out of; for a
standing wave plot it's a matter of the magnitude of current flowing
*AT* the specific positions. The current is alternating equally in both
directions. There isn't a *net* current flow.
73, Jim AC6XG
There exists no "reality" in which more current "goes in" one end of a
device than "comes out" the other.
But Jim, the original argument was that the current into the
coil is the same magnitude and phase as the current out of
the coil.
But Cecil, the original argument wouldn't have been as big an argument
if it had been more accurately stated. Or more precisely, if you hadn't
subsequently misstated the facts Yuri had disclosed. It's true that the
standing wave current at one end of the coil is greater than it is at
the other end. You and I both know why that is so. But there are only
so many ways that can be accurately stated before things begin to head
off into the ridiculous, the obtuse, and the sublime - directions you
have a marked propensity for taking. Reel it back in just a bit.
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