Guy has a good analogy.
BB: the "field" consists entirely of energy; there is no mass (weight
resulting from gravity) to a field. The field does contain "ripples" as Guy
says, with characteristics of amplitude (strength), velocity (speed which
varies according to what it's traveling through, vacuum being the fastest),
frequency (number of "ripples" per unit of time), and wavelength (distance
between the peaks of the "ripples". The electric and magnetic fields that
make of an electromagnetic wave field are typically oriented at right angles
to each other (there are ways that the "phase angle" between them can be
altered, but this is relatively rare).
Now, here's an interesting phenomenae that I mention only for interest, as
it typically is not considered (or necessary) in ham radio antenna and RF
communications: BOTH matter and energy are related as demonstrated in
Einstein's General Theory of Relativity and its famous equation E=MC^2 (C
squared), ie matter can be viewed as composed entirely of energy or energy
viewed as being matter. Likewise, both matter and energy can be viewed as
both particles and waves when moving (and even at rest at the quantum
level). Electrons, which consists of matter with mass, moving through the
wire of an antenna are instantly both particles and waves; their movement
produces electromagnetic energy "radiation" that is pure energy but also are
instantly both particles ("photons") and waves. IF the electrons are NOT
moving, ie "static", there is still an electric field and magnetic field
produced that is pure energy and consists of non-moving photons and a wave
of zero frequency, zero velocity, but with an amplitude and wavelength
("lines of force", you can view the magnetic lines of force and measure
their wavelength by putting a magnetic, whose electrons produce a magnetic
field based on relative spin of their componenets, under a surface on which
is placed iron filings; it's trickier to "see" the lines of force of an
electric field produced by an electrically charged body in the same way).
Charged bodies (eg a capacitor) produces an electric field that is commonly
referred to as "static electricity", eg when you rub a comb on a silk
polyester cloth and it makes your hair stand up is a demonstration of the
existence of this electric field, which is again *energy*, not mass, but
still consists of quantum photon/particle units.
Clear as mud? :-)
Here's a good starter book for laypeople on this topic, well written by a
journalist who hung around physicists: "The Dancing Wu Li Masters" by Gary
Zukav; it's a fun read.
http://www.amazon.com/Dancing-Wu-Li-Masters-Overview/dp/0060959681/ref=sr_1_
1?ie=UTF8&qid=1234726839&sr=1-1
For those fluent in math and basic physics, an interesting article: "Why
Antennas Radiate" by Stuart G. Downs, WY6EE, written Jan/Feb 2005 and
published in the April 2007 issue of AntenneX ezine (www.antennex.com).
73, Stephen
-----Original Message-----
From: antennaware-bounces@contesting.com
[mailto:antennaware-bounces@contesting.com] On Behalf Of Guy Olinger, K2AV
Sent: Sunday, February 15, 2009 8:25 AM
To: antennaware@contesting.com
Subject: Re: [Antennaware] Electrons
The often quoted rule: Movement of charge creates electromagnetic radiation.
If you move an electron from here to there it leaves three dimensional
"ripples", not entirely unlike the two dimensional effect of pulling the
point of a stick through the surface of a quiet pool.
There is such a thing as particle radiation with large amounts energy vested
in the velocity and mass of the particle. The most basic concept of
electromagnetic radiation and particle radiation are practically very
different things, though quantum physics ties them together mathematically.
The issues and principles discussed around particle radiation are not
practical for ham antenna design, rather the rule from the first sentence is
the essential basis for transformers and antennas from power frequencies to
way past microwave.
73, Guy
----- Original Message -----
From: "bumerang boom" <bumerang.boom@yahoo.com>
To: <antennaware@contesting.com>
Sent: Saturday, February 14, 2009 9:53 PM
Subject: [Antennaware] Electrons
> Hello :)
> This question is nagging me for a while now but I did not find yet an
> acceptable answer:
>
> Q: Where are the radiated electrons come from?
>
>
> Is a PhD in Physics in the house?
>
> BB
> Without Wax
>
>
>
>
>
>
> _______________________________________________
> Antennaware mailing list
> Antennaware@contesting.com
> http://lists.contesting.com/mailman/listinfo/antennaware
>
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