"joe" napisal w wiadomosci
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Szczepan Bialek wrote:
"Jim Lux" napisal w wiadomosci
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John - KD5YI wrote:

Again, I'm not sure "temperature" is the relevant measure for
something
like that. You can define temperature for a very low pressure gas like
this, but it's not in the same sort of sense as one would apply to a
bulk tangible medium (like air at the Earth's surface or water)
Isaac Asimov touched on this in his book on physics. He said the
temperature up there is high because of the high molecule velocity, but
that *heat* is another matter. So, you can have a high "temperature"
even if the "heat" is practically nil.

I suppose, too, that the whole things still works in terms of, say,
propagation velocity of sound, because that is driven by velocity of
molecules/atoms (and is related to square root of Temperature).

Faraday supposed that this apply to the electric waves.

He was wrong.

Why. Molecules and ions vibrate. Electrons also.

Of course there the
electrons vibrate. The relation to temperature of electrons would be easy
to measure.


No, you have this wrong.


So, sound propagates very quickly in the ionosphere (it's got a fairly
high temperature), but because there's not a whole lot of atoms around,
the attenuation will be quite high (essentially infinite, I suspect)

No. Acoustic waves from the Sun (aurora) are at the Earth quite strong.

"acoustic waves" whatever you think they are do not propagate through a
vacuum.

"The Earth is constantly immersed in the solar wind, a rarefied flow of hot
plasma (gas of free electrons and positive ions) emitted by the Sun in all
directions, a result of the two-million-degree heat of the Sun's outermost
layer, the corona. The solar wind usually reaches Earth with a velocity
around 400 km/s, density around 5 ions/cm3 and magnetic field intensity
around 2-5 nT (nanoteslas; Earth's surface field is typically 30,000-50,000
nT). These are typical values. During magnetic storms, in particular, flows
can be several times faster; the interplanetary magnetic field (IMF) may
also be much stronger."

The aurora is NOT caused by acoustic waves.

" In the explosive event that a coronal mass ejection (CME) is reported it's
time to hop into action because this super-charged solar wind is traveling
fast (maybe 3-to-5 million miles per hour). When this energy sweeps by the
earth 1-to-3 nights later there is a very good chance of aurora activity".
From: http://aurorahunter.com/aurora-prediction.php

Do you think that ions and atoms in the solar wind do not vibrate?



And that's totally different than propagating something by EM waves.

Electric waves propagate in metal and in space. In the both media the
electrons vibrate.

But that is not how the waves propagate. In either material.

How then?


"I suppose we may compare together the matter of the
aether and ordinary matter (as, for instance, the copper of the wire
through which the electricity is conducted), and consider them as alike
in their essential constitution"(Faraday).

But this is wrong. You refuse to accept that 100+ year old statements may
be, and quite often are, wrong.

Heaviside's statements are also old.


That makes you correct. One must carefully state what is meant by
temperature and what is meant by heat.

It would be easy after Schmidt's experiment in vacuum. There the hot
cylider in air bends the light rays and the shadow diameter is bigger
than for the cold cylinder.
The same experiment in vacuum tell us if speed of light is electrons
temperature dependent.

If you spent some time to understand the basic concepts, you might realize
just how wrong you are.


What is the point of all this? You refuse to try to understand the basic
concepts, yet want to dig into the more esoteric stuff.

The topic is: " It was known that different frequencies travel with
different speeds on a
long cable".

Is the same in air and space?"

The answers were YES.

What do you want to add?
S*