Why no magnetic force on a charge at rest?

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Why no magnetic force on a charge at rest?

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Rolf Wilms

Posted: Mon Dec 22, 2003 8:07 pm

Guest

To my excitement I've read that the magnetic field is really a relativistic
effect of the electric field, due to Lorentz contraction observed by a
moving charge. What puzzels me now is that this effect only applies to
moving charges.

If we consider a conductor, say a metal, through which a current flows, the
negative electrons move and transport the charge and the positive nuclei are
at rest. Thus for a probe charge - also at rest - outside the conductor, the
electrons moving inside the conductor should appear Lorentz-contracted thus
having a higher density than the positive nuclei. So the conductor should
appear negatively charged to the probe.

I'm sure I'm making a mistake in the above, but where?

Thanks,
Rolf

Brian Trosko

Posted: Mon Dec 22, 2003 8:07 pm

Guest

Robert J. Kolker <bobkolker@attbi.com> wrote:

[quote:3361a99ef8]Uncle Al wrote:

has been elevated from teal to peuce! Officals mightily dread one
further increment to the most terrible terror level of all: argyle.

It would be a cyan if they went to argyle.
[/quote:3361a99ef8]
Teal me about it.

Uncle Al

Posted: Mon Dec 22, 2003 9:10 pm

Guest

Rolf Wilms wrote:
[quote:0cef4abd72]
To my excitement I've read that the magnetic field is really a relativistic
effect of the electric field, due to Lorentz contraction observed by a
moving charge. What puzzels me now is that this effect only applies to
moving charges.

If we consider a conductor, say a metal, through which a current flows, the
negative electrons move and transport the charge and the positive nuclei are
at rest. Thus for a probe charge - also at rest - outside the conductor, the
electrons moving inside the conductor should appear Lorentz-contracted thus
having a higher density than the positive nuclei. So the conductor should
appear negatively charged to the probe.
[/quote:0cef4abd72]
You are confusing phase vs. group velocities. The signal travels at
near lightspeed divided by the square root of the peripheral
dielectric constant. The electrons in any reasonable wire travel a
few to a few dozen microns/second. If you had relativistic electrons
flowing through the conductor, their scattering off the stationary
nuclei would invalidate the experiment.

More to the point - what about the current in paricle accelerators?
Do the apparent number of coulombs of particles increase as the beam
is accelerated?

HOT OFF THE TV NEWS! The San Francisco terrorist warning color level
has been elevated from teal to peuce! Officals mightily dread one
further increment to the most terrible terror level of all: argyle.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!

Robert J. Kolker

Posted: Mon Dec 22, 2003 9:50 pm

Guest

Uncle Al wrote:

[quote:b04f6ff3bb]has been elevated from teal to peuce! Officals mightily dread one
further increment to the most terrible terror level of all: argyle.
[/quote:b04f6ff3bb]
It would be a cyan if they went to argyle.

Bob Kolker

Paul R. Mays

Posted: Mon Dec 22, 2003 10:00 pm

Guest

"Brian Trosko" <btrosko@panix.com> wrote in message
news:bs8ajo$dqn$3@reader2.panix.com...
[quote:ebd64fe415]Robert J. Kolker <bobkolker@attbi.com> wrote:

Uncle Al wrote:

has been elevated from teal to peuce! Officals mightily dread one
further increment to the most terrible terror level of all: argyle.

It would be a cyan if they went to argyle.

Teal me about it.
[/quote:ebd64fe415]
Yes it would be a Black day indeed...

Franz Heymann

Posted: Tue Dec 23, 2003 1:31 am

Guest

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3FE7A42F.B5BF850F@hate.spam.net...
[quote:8747cfdfb5]Rolf Wilms wrote:

To my excitement I've read that the magnetic field is really a
relativistic
effect of the electric field, due to Lorentz contraction observed by a
moving charge. What puzzels me now is that this effect only applies to
moving charges.

If we consider a conductor, say a metal, through which a current flows,
the
negative electrons move and transport the charge and the positive nuclei
are
at rest. Thus for a probe charge - also at rest - outside the conductor,
the
electrons moving inside the conductor should appear Lorentz-contracted
thus
having a higher density than the positive nuclei. So the conductor
should
appear negatively charged to the probe.

You are confusing phase vs. group velocities. The signal travels at
near lightspeed divided by the square root of the peripheral
dielectric constant. The electrons in any reasonable wire travel a
few to a few dozen microns/second. If you had relativistic electrons
flowing through the conductor, their scattering off the stationary
nuclei would invalidate the experiment.

More to the point - what about the current in paricle accelerators?
Do the apparent number of coulombs of particles increase as the beam
is accelerated?

HOT OFF THE TV NEWS! The San Francisco terrorist warning color level
has been elevated from teal to peuce! Officals mightily dread one
further increment to the most terrible terror level of all: argyle.

[/quote:8747cfdfb5]
Uncle Al must have been pissed again when he wrote that crap.

Franz

Mark Fergerson

Posted: Tue Dec 23, 2003 2:16 am

Guest

Uncle Al wrote:
[quote:7fbefd1e5c]Rolf Wilms wrote:

To my excitement I've read that the magnetic field is really a relativistic
effect of the electric field, due to Lorentz contraction observed by a
moving charge. What puzzels me now is that this effect only applies to
moving charges.

If we consider a conductor, say a metal, through which a current flows, the
negative electrons move and transport the charge and the positive nuclei are
at rest. Thus for a probe charge - also at rest - outside the conductor, the
electrons moving inside the conductor should appear Lorentz-contracted thus
having a higher density than the positive nuclei. So the conductor should
appear negatively charged to the probe.

You are confusing phase vs. group velocities. The signal travels at
near lightspeed divided by the square root of the peripheral
dielectric constant. The electrons in any reasonable wire travel a
few to a few dozen microns/second. If you had relativistic electrons
flowing through the conductor, their scattering off the stationary
nuclei would invalidate the experiment.
[/quote:7fbefd1e5c]
I think Rolf's visualizing pancake-shaped electrons (axes
parallel to current vector) that can pack closer than
spherical ones. Bad.

[quote:7fbefd1e5c]More to the point - what about the current in paricle accelerators?
Do the apparent number of coulombs of particles increase as the beam
is accelerated?
[/quote:7fbefd1e5c]
At first glance it should actually _decrease_ as the
particles' deBroglie wavelength got shorter; you'd see
elements of fewer electrons' wavefunctions in an
"instantaneous" snapshot of the beam cross-section. But the
rub is the words "instantaneous" and "cross-section".

[quote:7fbefd1e5c]HOT OFF THE TV NEWS! The San Francisco terrorist warning color level
has been elevated from teal to peuce! Officals mightily dread one
further increment to the most terrible terror level of all: argyle.
[/quote:7fbefd1e5c]
Given the uneven response lag across the country, how
long does the Nation spend in a transitional "plaid" state
after a threat level change is announced?

Mark L. Fergerson

Rolf Wilms

Posted: Tue Dec 23, 2003 6:00 am

Guest

Uncle Al wrote:

[quote:f740eaba39]You are confusing phase vs. group velocities. The signal travels at
near lightspeed divided by the square root of the peripheral
dielectric constant. The electrons in any reasonable wire travel a
few to a few dozen microns/second. If you had relativistic electrons
flowing through the conductor, their scattering off the stationary
nuclei would invalidate the experiment.
[/quote:f740eaba39]
You seem to assume that relativistic electron speeds in the conductor were
needed for the Lorentz force, but this is not so. If it was, we had no
magnetism at all. See i.e.
http://physics.weber.edu/schroeder/mrr/MRRtalk.html "Magnetism as a
Consequence of Length Contraction" or let me cite Feynman:
"Also, if we estimate the velocities of the electrons in the wire, we find
that their average speed along the wire is about 0.01 centimeter per second.
So v^2/c^2 is about 1E-25. Surely a negligible 'correction'. But no!"

[quote:f740eaba39]More to the point - what about the current in paricle accelerators?
Do the apparent number of coulombs of particles increase as the beam
is accelerated?
[/quote:f740eaba39]
We know that the charge is invariant, thus the number of coulombs doesn't
change. But the charge density increases because of the Lorentz contraction.
The otherwise spherical shape of the electrons' fields takes the form of a
pancake. Again see http://physics.weber.edu/schroeder/mrr/MRRtalk.html
"Transformation of Electrostatic Fields"
I probably wasn't precise enough when I said "the conductor should appear
negatively charged to the probe". What I meant to say is that the probe
should observe an electric field. When there is no current flowing through
the conductor, the positive and negative fields cancel out. But when the
electrons are moving, their charge density increases so that the fields
don't cancel out.

Thanks,
Rolf

Titan Point

Posted: Tue Dec 23, 2003 6:14 am

Guest

"Robert J. Kolker" <bobkolker@attbi.com> wrote in message news:<bs8ah4$anvgf$2@ID-76471.news.uni-berlin.de>...
[quote:bbbf53eebc]Uncle Al wrote:

has been elevated from teal to peuce! Officals mightily dread one
further increment to the most terrible terror level of all: argyle.

It would be a cyan if they went to argyle.

Bob Kolker
[/quote:bbbf53eebc]
I'll see your argyle and raise you paisley!

Aaaaarrrrrrgggggghhhhhh!

Robert J. Kolker

Posted: Tue Dec 23, 2003 10:41 am

Guest

Brian Trosko wrote:

[quote:29c2c50182]
Teal me about it.
[/quote:29c2c50182]
I red about it in the papers and it made me blue. It is enough to make
one purple with rage, white with anger and green with envy. And it is
all the fault of those yellow bastards.

Bob Kolker

Bruce Bowen

Posted: Tue Dec 23, 2003 12:42 pm

Guest

"Rolf Wilms" <rolf_wilms@hotmail.com> wrote in message news:<3fe7955c_2@news.arcor-ip.de>...
[quote:2e59b25a72]To my excitement I've read that the magnetic field is really a relativistic
effect of the electric field, due to Lorentz contraction observed by a
moving charge. What puzzels me now is that this effect only applies to
moving charges.

If we consider a conductor, say a metal, through which a current flows, the
negative electrons move and transport the charge and the positive nuclei are
at rest. Thus for a probe charge - also at rest - outside the conductor, the
electrons moving inside the conductor should appear Lorentz-contracted thus
having a higher density than the positive nuclei. So the conductor should
appear negatively charged to the probe.
[/quote:2e59b25a72]
The key word here is "conductor". The electrons automatically
distribute themselves (since they are free to flow) in such a way as
to eliminate charge. They are not rigidly held in possition with
respect to each other, hence their density is independent of their
velocity.

-Bruce

S. Enterprize Company

Posted: Tue Dec 23, 2003 1:54 pm

Guest

[quote:e5449627af]To my excitement I've read that the magnetic field is really a relativistic
effect of the electric field, due to Lorentz
[/quote:e5449627af]
This is incorrect according to The Smart Model Theory. The electric fields is
caused by the oscillations of the internal charge sub-atomic capacitance which
is located at the core of proton or electron. This charge has been referred to
as quarks, but it is called "Smarks" with regard to the Smart Model. The
Magnetic field is associated with the Helix Spiral Field internally that works
also with the sub-atomic oscillators of the Smart Model. The "Smark" sub-atomic
capacitance fields are perpendicular to the Helix Spiral fields that causes the
magnetic fields. The Core of the Smart Model particle or atom has a high
sub-atomic hollow pressure zone in the Smart Model Neutral particle area this
contributes to the mass and the sub-atomic resistance for a particle or atom.
So put this together and what do you have? An sub-atomic oscillator circuit
that continually moves perpetually measures with energy in eV's. But this
oscillator must have an Aether Fluid to form the particle itself. You just
don't have a point particle or a quantum vacuum. THERE IS REALLY SOMETHING
THERE.

http://members.aol.com/smart314159/SubAtomicCircuit.jpg

Electric Fields, Magnetic Fields, mass and charge are separate entities. An
EM field is caused EXTERNALLY as the Smart Model sub-atomic oscillator radiates
energy around it.

The Smart Model IS in AGREEMENT with classical physics in that, energy IS
radiated from a particle or atom. QM assumes that this doesn't occur, even
though they know it does, but they can't explain their QM model with it
radiating energy. SO they say just ignore this for now to make things simple.
Well this is because the QM model is incorrect and so is the Standard
Model.

There is ONLY one correct atomic model and that is THE SMART MODEL.

contraction observed by a
[quote:e5449627af]moving charge. What puzzels me now is that this effect only applies to
moving charges.
[/quote:e5449627af]

Smart's Alt. Physics News Group
http://pub39.bravenet.com/forum/show.php?usernum=3320272813&cpv=1
S. Enterprize (Science Journal)
http://smart1234.s-enterprize.com/

Jim Black

Posted: Tue Dec 23, 2003 3:20 pm

Guest

"Rolf Wilms" <rolf_wilms@hotmail.com> wrote in message news:<3fe7955c_2@news.arcor-ip.de>...
[quote:42ab2d9a4b]To my excitement I've read that the magnetic field is really a relativistic
effect of the electric field, due to Lorentz contraction observed by a
moving charge. What puzzels me now is that this effect only applies to
moving charges.

If we consider a conductor, say a metal, through which a current flows, the
negative electrons move and transport the charge and the positive nuclei are
at rest. Thus for a probe charge - also at rest - outside the conductor, the
electrons moving inside the conductor should appear Lorentz-contracted thus
having a higher density than the positive nuclei. So the conductor should
appear negatively charged to the probe.

I'm sure I'm making a mistake in the above, but where?

Thanks,
Rolf
[/quote:42ab2d9a4b]
In a neutral wire carrying current, there are equal numbers of protons
and electrons in the same length of wire. Thus, there is no force on
the test charge.

t
^ + - + - + - + - + - + -
| | / | / | / | / | / | /
| |/ |/ |/ |/ |/ |/
| | | | | | |
| /| /| /| /| /| /|
| / | / | / | / | / | / |
| / | / | / | / | / | / |
| | / | / | / | / | / | /
| |/ |/ |/ |/ |/ |/
| | | | | | |
| /| /| /| /| /| /|
| / | / | / | / | / | / |
| / | / | / | / | / | / |
| | / | / | / | / | / | /
| |/ |/ |/ |/ |/ |/
| | | | | | |
| /| /| /| /| /| /|
-----------------------------------------------> x

Let's now make the test charge an electron and have it moving parallel
to the wire at the same speed and direction as the electrons in the
wire. To determine the force on the test charge, we move to the frame
of reference of the test charge.

t'
^
/
/
t /
^ + - + - + - + - + - + -
| | / | / | / | / | / | /
| |/ |/ |/ |/ |/ |/
| | | | | | _|
| /| /| /| /| /|__--/|
| / | / | / | / | __--```/ | __-> x'
| / | / | / | / __--/``|``/ | __--
| | / | / |__--`|`/```|`/ |__--
| |/ |/ __--/````|/````|/ __--/
| | |--```|`````|````_/-- |
| /| /|````/|````/|__--/| /|
| / | /`|```/`|``__-- / | / |
| / | /``|``/`__--/ | / | / |
| | /```|__-- | / | / | / | /
| |/`__--/ |/ |/ |/ |/
| |-- | | | | |
| /| /| /| /| /| /|
-----------------------------------------------> x

t'
^
|
|
|
+- + - + -+ +-
\-----\-|---\---|-\-----\
|\`````\|````\``|``\````|
|`\`````\`````\`|```\```|
|``\````|\`````\|````\``|
|```\```|`\`````\`````\`|
|````\``|``\````|\`````\|
\-----\-|---\---|-\-----\---------> x'

The protons are closer together than the electrons in this frame of
reference.

INSTANT IN THE TEST CHARGE'S FRAME
later
(in lab frame time)
<------------------- direction of
___________ electron flow
- | | +
- | | +
- | || | +
___ || | +
- _||_ | + (-) test charge
- | \ / | +
- | \/ | +
- |__________| +

earlier
(in lab frame time)

The entire circuit still has an overall neutral charge. But because
of relativity of simultaneity, at an instant in the test charge's
frame, the side closer to the test charge appears to have a slight
positive charge, while the other side appears to have a slight
negative charge. This is because, at this instant, the time at the
top end of the loop (as measured by the "stationary" clocks in the
laboratory) is later. That means that the electrons on the top side
have had more time to flow out of the right side that the electrons on
the bottom side have had to flow into it.

- Jim E. Black

S. Enterprize Company

Posted: Tue Dec 23, 2003 3:27 pm

Guest

[quote:e2cf14607d]"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3FE7A42F.B5BF850F@hate.spam.net...
Rolf Wilms wrote:

To my excitement I've read that the magnetic field is really a
relativistic
effect of the electric field, due to Lorentz contraction observed by a
moving charge. What puzzels me now is that this effect only applies to
moving charges.

If we consider a conductor, say a metal, through which a current flows,
the
negative electrons move and transport the charge and the positive nuclei
are
at rest. Thus for a probe charge - also at rest - outside the conductor,
the
electrons moving inside the conductor should appear Lorentz-contracted
thus
having a higher density than the positive nuclei. So the conductor
should
appear negatively charged to the probe.

You are confusing phase vs. group velocities. The signal travels at
near lightspeed divided by the square root of the peripheral
dielectric constant. The electrons in any reasonable wire travel a
few to a few dozen microns/second. If you had relativistic electrons
flowing through the conductor, their scattering off the stationary
nuclei would invalidate the experiment.

More to the point - what about the current in paricle accelerators?
Do the apparent number of coulombs of particles increase as the beam
is accelerated?

HOT OFF THE TV NEWS! The San Francisco terrorist warning color level
has been elevated from teal to peuce! Officals mightily dread one
further increment to the most terrible terror level of all: argyle.

Uncle Al must have been pissed again when he wrote that crap.

Franz

[/quote:e2cf14607d]
Uncle Al appears to be always pissed. If he understood the Smart Model he
would have tranquility and scientific peace again.

Smart's Alt. Physics News Group
http://pub39.bravenet.com/forum/show.php?usernum=3320272813&cpv=1
S. Enterprize (Science Journal)
http://smart1234.s-enterprize.com/

S. Enterprize Company

Posted: Tue Dec 23, 2003 3:31 pm

Guest

[quote:c5403b5594]"Rolf Wilms" <rolf_wilms@hotmail.com> wrote in message
news:<3fe7955c_2@news.arcor-ip.de>...
To my excitement I've read that the magnetic field is really a relativistic
effect of the electric field, due to Lorentz contraction observed by a
moving charge. What puzzels me now is that this effect only applies to
moving charges.

If we consider a conductor, say a metal, through which a current flows, the
negative electrons move and transport the charge and the positive nuclei
are
at rest. Thus for a probe charge - also at rest - outside the conductor,
the
electrons moving inside the conductor should appear Lorentz-contracted thus
having a higher density than the positive nuclei. So the conductor should
appear negatively charged to the probe.

The key word here is "conductor". The electrons automatically
distribute themselves (since they are free to flow) in such a way as
to eliminate charge. They are not rigidly
[/quote:c5403b5594]

Nope, electrons don't eliminate charge. There are two types of charge
according to the Smart Model Theory, 1) internally and 2) externally.

Internally the charge remains constant. Externally it is just a state where
balance or steady state is reached.

held in possition with
[quote:c5403b5594]respect to each other, hence their density is independent of their
velocity.

-Bruce
[/quote:c5403b5594]

Smart's Alt. Physics News Group
http://pub39.bravenet.com/forum/show.php?usernum=3320272813&cpv=1
S. Enterprize (Science Journal)
http://smart1234.s-enterprize.com/

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