| Topic: |
Science > Physics |
| User: |
"xray4abc" |
| Date: |
15 Nov 2006 02:01:28 PM |
| Object: |
Simple electricity, and yet.....! |
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
All the best, LL
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| User: "Sorcerer" |
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| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 03:15:46 PM |
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"xray4abc" <lemhenyil@yahoo.ca> wrote in message
news:1163620888.625245.162710@b28g2000cwb.googlegroups.com...
| Consider an ideal metallic conductor, connected,
| in a closed electrical circuit, to a non-ideal DC
| power source.
| E=0 inside the conductor;
Whoa! Where did you get that idea?
Consider a vacuum tube such as a TV, connected,
in a closed electrical circuit, to a non-ideal DC
power source such as voltage tripler.
E=26,000 V at one end of the vacuum and E = -5V at the other end.
E and B are perpendicular to each other inside the vacuum.
What is, then, causing the electrical current through
the vacuum? What is pushing the electrons along the beam?
Why is the grid voltage zero and stopping them dead ?
Why does the cathode have a fluctuating voltage?
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| User: "Dirk Van de moortel" |
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| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 03:41:38 PM |
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"Sorcerer" <Headmaster@hogwarts.physics_e> wrote in message news:6sL6h.166062$lT5.139215@fe2.news.blueyonder.co.uk...
"xray4abc" <lemhenyil@yahoo.ca> wrote in message
news:1163620888.625245.162710@b28g2000cwb.googlegroups.com...
| Consider an ideal metallic conductor, connected,
| in a closed electrical circuit, to a non-ideal DC
| power source.
| E=0 inside the conductor;
Whoa! Where did you get that idea?
Consider a vacuum tube such as a TV, connected,
in a closed electrical circuit, to a non-ideal DC
power source such as voltage tripler.
E=26,000 V at one end of the vacuum and E = -5V at the other end.
E and B are perpendicular to each other inside the vacuum.
What is, then, causing the electrical current through
the vacuum? What is pushing the electrons along the beam?
Why is the grid voltage zero and stopping them dead ?
Why does the cathode have a fluctuating voltage?
Brilliant:
"The vacuum tube as an ideal metallic conductor":
http://users.telenet.be/vdmoortel/dirk/Physics/Fumbles/VacuumTube.html
Dirk Vdm
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| User: "Sorcerer" |
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| Title: Re: Simple electricity, and yet.....! |
16 Nov 2006 12:30:26 AM |
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"Dirk Van de moortel" <dirkvandemoortel@ThankS-NO-SperM.hotmail.com> wrote
in message news:mQL6h.186711$ds3.2960410@phobos.telenet-ops.be...
[anip]
Go mumble about Ghost and Patrick Swayze, that's more your level,
you sure don't know any physics.
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| User: "John C. Polasek" |
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| Title: Re: Simple electricity, and yet.....! |
16 Nov 2006 03:36:57 PM |
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On 15 Nov 2006 12:01:28 -0800, "xray4abc" <lemhenyil@yahoo.ca> wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
All the best, LL
If the resistance of the load is zero, you are dealing with a constant
current source not a voltage source. It is no different than shorting
the battery: the full voltage across the internal R, forces I = V/R.
If you happen to supply an equivalent connection to the negative
terminal it msut carry the same current as V/R.
You were pleased to see that the shorted battery obeyed Ohm's law and
should not be surprised to see your shorting wire is carrying that
current.
Your reference to Poynting's vector is misplaced I believe because PV
should be restricted to waves in space. You should be able to see that
you are delivering zero power to the wire: it's all going into heating
the battery.
The battery is both a ready source of electrons and at the other
terminal a ready receptor for electrons. You are simply facilitating
the transfer.
John Polasek
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| User: "xray4abc" |
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| Title: Re: Simple electricity, and yet.....! |
16 Nov 2006 05:02:43 PM |
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John C. Polasek wrote:
On 15 Nov 2006 12:01:28 -0800, "xray4abc" <lemhenyil@yahoo.ca> wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
All the best, LL
If the resistance of the load is zero, you are dealing with a constant
current source not a voltage source. It is no different than shorting
the battery: the full voltage across the internal R, forces I = V/R.
If you happen to supply an equivalent connection to the negative
terminal it msut carry the same current as V/R.
You were pleased to see that the shorted battery obeyed Ohm's law and
should not be surprised to see your shorting wire is carrying that
current.
Your reference to Poynting's vector is misplaced I believe
You got this wrong for sure!
It can be shown that U*I, which is the power dissipated by a
resistor can be found by calculating the Pointing's vector flux through
a
plane perpendicular to the pair of supply conductors (supposed to be
parallel one to another)
because PV
should be restricted to waves in space. You should be able to see that
you are delivering zero power to the wire: it's all going into heating
the battery.
The battery is both a ready source of electrons and at the other
terminal a ready receptor for electrons. You are simply facilitating
the transfer.
And what makes the conductor "wish" to have a transfer of
electrons?
John Polasek
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| User: "John C. Polasek" |
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| Title: Re: Simple electricity, and yet.....! |
17 Nov 2006 12:59:28 PM |
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On 16 Nov 2006 15:02:43 -0800, "xray4abc" <lemhenyil@yahoo.ca> wrote:
John C. Polasek wrote:
On 15 Nov 2006 12:01:28 -0800, "xray4abc" <lemhenyil@yahoo.ca> wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
All the best, LL
If the resistance of the load is zero, you are dealing with a constant
current source not a voltage source. It is no different than shorting
the battery: the full voltage across the internal R, forces I = V/R.
If you happen to supply an equivalent connection to the negative
terminal it msut carry the same current as V/R.
You were pleased to see that the shorted battery obeyed Ohm's law and
should not be surprised to see your shorting wire is carrying that
current.
Your reference to Poynting's vector is misplaced I believe
You got this wrong for sure!
It can be shown that U*I, which is the power dissipated by a
resistor can be found by calculating the Pointing's vector flux through
a
plane perpendicular to the pair of supply conductors (supposed to be
parallel one to another)
because PV
should be restricted to waves in space. You should be able to see that
you are delivering zero power to the wire: it's all going into heating
the battery.
The battery is both a ready source of electrons and at the other
terminal a ready receptor for electrons. You are simply facilitating
the transfer.
And what makes the conductor "wish" to have a transfer of
electrons?
John Polasek
JP:
I didn't see you asking about the power into the resistor before; you
were interested in the zero load resistance carrying current.
The entire loop possesses an irreducible inductance L, making a
circuit with a time constant of T = L/R seconds. There will be an
initial buildup of energy as the current rises by V/R*(1-exp t/T) and
that energy will be present in the drift momentum of all the
electrons.
During the transient, there will be fleeting voltage V/R*exp t/T
across the inductance of the wire. The free transportation of which
you are suspicious is simply constancy of momentum.
John Polasek
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| User: "xray4abc" |
|
| Title: Re: Simple electricity, and yet.....! |
17 Nov 2006 07:55:23 PM |
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|
John C. Polasek wrote:
On 16 Nov 2006 15:02:43 -0800, "xray4abc" <lemhenyil@yahoo.ca> wrote:
John C. Polasek wrote:
On 15 Nov 2006 12:01:28 -0800, "xray4abc" <lemhenyil@yahoo.ca> wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
All the best, LL
If the resistance of the load is zero, you are dealing with a constant
current source not a voltage source. It is no different than shorting
the battery: the full voltage across the internal R, forces I = V/R.
If you happen to supply an equivalent connection to the negative
terminal it msut carry the same current as V/R.
You were pleased to see that the shorted battery obeyed Ohm's law and
should not be surprised to see your shorting wire is carrying that
current.
Your reference to Poynting's vector is misplaced I believe
You got this wrong for sure!
It can be shown that U*I, which is the power dissipated by a
resistor can be found by calculating the Pointing's vector flux through
a
plane perpendicular to the pair of supply conductors (supposed to be
parallel one to another)
because PV
should be restricted to waves in space. You should be able to see that
you are delivering zero power to the wire: it's all going into heating
the battery.
The battery is both a ready source of electrons and at the other
terminal a ready receptor for electrons. You are simply facilitating
the transfer.
And what makes the conductor "wish" to have a transfer of
electrons?
John Polasek
JP:
I didn't see you asking about the power into the resistor before; you
were interested in the zero load resistance carrying current.
The entire loop possesses an irreducible inductance L, making a
circuit with a time constant of T = L/R seconds. There will be an
initial buildup of energy as the current rises by V/R*(1-exp t/T) and
that energy will be present in the drift momentum of all the
electrons.
During the transient, there will be fleeting voltage V/R*exp t/T
across the inductance of the wire. The free transportation of which
you are suspicious is simply constancy of momentum.
John Polasek
OK.
Let's consider a different situation.
Let be 2 electrically charged metallic bodies separated in vacuum.
If there is a free charge-holder between the two bodies, initially
at rest, its further movement (if no other influences occur) will
be along a line of the electric field of the considered bodies.
Traditionally, we attribute the quality of being a form of matter
to the
electrical field and as such we understand who/what is
exerting the action/force on the charge-holder in this case.
(and of course we do not ask other questions with no clear
answers until now, as the ones referring to the relation between
aether, vacuum, electric field, magnetic field etc)
In the other example considered earlier, you say that
the source is doing this. Yes, but how?
( Constancy of momentum?, yes, but this momentum
has to be obtained from somewhere.)
The same way one could say that the 2 charged bodies
are accelerating the above considered mobile charge-holder,
which is kind of inaccurate.
Sure, again, traditionally we were talking about electromotive
force and let the calculations do the rest.
Form a practical point of view, this is good enough.
Not for me right now as I am trying to dig a little bit deeper.
I think that the Poynting vector shows something deep
and troubling concerning electromagnetism.
Namely, whenever energy transport occurs involving electric or
magnetic fields, both E and B (or H) are present !
I am trying to figure out if and how can/could this happen!
I have some ideas, partially disclosed in other threads
(like the one referring to the nature of the vacuum) and
I am playing with them while gathering information.
I am glad that I could find folks interested
enough and polite enough to have decent exchange of
ideas in this group! ( The others......do not matter!)
All the best, LL
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| User: "John C. Polasek" |
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| Title: Re: Simple electricity, and yet.....! |
18 Nov 2006 02:01:38 PM |
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On 17 Nov 2006 17:55:23 -0800, "xray4abc" <lemhenyil@yahoo.ca> wrote:
John C. Polasek wrote:
On 16 Nov 2006 15:02:43 -0800, "xray4abc" <lemhenyil@yahoo.ca> wrote:
John C. Polasek wrote:
On 15 Nov 2006 12:01:28 -0800, "xray4abc" <lemhenyil@yahoo.ca> wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
All the best, LL
If the resistance of the load is zero, you are dealing with a constant
current source not a voltage source. It is no different than shorting
the battery: the full voltage across the internal R, forces I = V/R.
If you happen to supply an equivalent connection to the negative
terminal it msut carry the same current as V/R.
You were pleased to see that the shorted battery obeyed Ohm's law and
should not be surprised to see your shorting wire is carrying that
current.
Your reference to Poynting's vector is misplaced I believe
You got this wrong for sure!
It can be shown that U*I, which is the power dissipated by a
resistor can be found by calculating the Pointing's vector flux through
a
plane perpendicular to the pair of supply conductors (supposed to be
parallel one to another)
because PV
should be restricted to waves in space. You should be able to see that
you are delivering zero power to the wire: it's all going into heating
the battery.
The battery is both a ready source of electrons and at the other
terminal a ready receptor for electrons. You are simply facilitating
the transfer.
And what makes the conductor "wish" to have a transfer of
electrons?
John Polasek
JP:
I didn't see you asking about the power into the resistor before; you
were interested in the zero load resistance carrying current.
The entire loop possesses an irreducible inductance L, making a
circuit with a time constant of T = L/R seconds. There will be an
initial buildup of energy as the current rises by V/R*(1-exp t/T) and
that energy will be present in the drift momentum of all the
electrons.
During the transient, there will be fleeting voltage V/R*exp t/T
across the inductance of the wire. The free transportation of which
you are suspicious is simply constancy of momentum.
John Polasek
OK.
Let's consider a different situation.
No I'm staying with the wire carrying current.
snip
I think that the Poynting vector shows something deep
and troubling concerning electromagnetism.
Namely, whenever energy transport occurs involving electric or
magnetic fields, both E and B (or H) are present !
I am trying to figure out if and how can/could this happen!
The Poynting vector is only present for the brief moment of the
transients I described above namely Vexp(-t/T) which would be the
power input to get the electrons moving. Incidentally V = L di/dt =
Ndphi/dt, where phi is the flux, phi = H*mu0.
E and H are always present together (in empty space and always in the
numerical ratio Z) because one causes the other (and back again). You
will find that empty space has an impedance of Z = 377 ohms and that
H = E/Z or
H ampturns/meter = Evoltspermeter/Z ohms.
E causes H via a tensor Z (that I can't quite get to work). Curl H =
dD/dt = eps0dE/dt.
I have some ideas, partially disclosed in other threads
(like the one referring to the nature of the vacuum) and
I am playing with them while gathering information.
I am glad that I could find folks interested
enough and polite enough to have decent exchange of
ideas in this group! ( The others......do not matter!)
All the best, LL
For your information, if you are studying the vacuu;m using the cgs
system, switch to SI, because you will never learn anything about the
vacuum. It was all written off when the Visigoths dumped eps0 by
implanting it (4pieps0) into the coulomb charge, which thereafter was
never a coulomb again, becoming instead an "electrostatic unit" whose
denomination is in volt-meters. Stick to the SI units.
John Polasek
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| User: "Timo Nieminen" |
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| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 04:52:21 PM |
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On Thu, 15 Nov 2006, xray4abc wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
For a PEC, yes, E=0 inside. In your example, E=0 outside as well (what
about B?). The current in the circuit is limited by the internal
resistance of the power supply - the voltage drop due to the current and
the internal resistance is equal to the open-circuit voltage of the
supply. so there is no potential difference across the two terminals, and
hence E=0 outside the power supply. Since there is a current in the
resistive power supply, there's an electric field in there. When the
electron exits the -ve terminal, it's still moving, and enters the wire,
where nothing impedes its motion.
Thus, you can assume that the current in the wire is ballistic motion of
the electrons spat out by the power supply.
PEC is an idealisation; so what if predictions made using it don't always
match reality - as long as you know how far you can push the idealisation,
all is well. Instead of beginning with a PEC conductor, start with a
finite conductivity, and see what happends when conductivity -> infinity.
Does this give you behaviour approximating a superconductor? Or is that
better described as a perfect magnetic conductor (PMC)? There was a paper
in J. Electromag. Waves and Applications, 2005, vol 19(7) by Lindell &
Sihvola about PEMC media; if you can cope a heavy dose of differential
forms, it might be of interest.
--
Timo Nieminen - Home page: http://www.physics.uq.edu.au/people/nieminen/
E-prints: http://eprint.uq.edu.au/view/person/Nieminen,_Timo_A..html
Shrine to Spirits: http://www.users.bigpond.com/timo_nieminen/spirits.html
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| User: "Randy Poe" |
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| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 02:20:08 PM |
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xray4abc wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
If E is zero everywhere inside the conductor, including where
it attaches to the source, then grad V is also zero. That is, there
is no voltage difference across the conductor and no current.
On the other hand, if you claim there is indeed a different
voltage at the two ends of the conductor, then obviously
E is not 0 everywhere.
Your initial conditions violate E = - grad V.
- Randy
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| User: "Sorcerer" |
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| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 03:36:25 PM |
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|
"Randy Poe" <poespam-trap@yahoo.com> wrote in message
news:1163622008.628004.128590@m73g2000cwd.googlegroups.com...
|
| xray4abc wrote:
| > Consider an ideal metallic conductor, connected,
| > in a closed electrical circuit, to a non-ideal DC
| > power source.
| > E=0 inside the conductor; E and B are perpendicular
| > to the conductor outside the conductor and at its surface too.
| >
| > What is, then, causing the electrical current through
| > the conductor? What is pushing the electrons along
| > the conductor?
|
| If E is zero everywhere inside the conductor, including where
| it attaches to the source, then grad V is also zero. That is, there
| is no voltage difference across the conductor and no current.
|
| On the other hand, if you claim there is indeed a different
| voltage at the two ends of the conductor, then obviously
| E is not 0 everywhere.
|
| Your initial conditions violate E = - grad V.
|
| - Randy
Maybe it's an ideal superconducting metallic conductor. LOL!
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| User: "xray4abc" |
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| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 04:56:52 PM |
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|
Randy Poe wrote:
xray4abc wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
If E is zero everywhere inside the conductor, including where
it attaches to the source, then grad V is also zero. That is, there
is no voltage difference across the conductor and no current.
Sorry, you are wrong!
In a simple DC circuit where e= I(R+r), if you have R=0
you still get I= e/r , where r is the internal resistance/ impedance
of the DC source and "e" is the open circuit voltage of the source.
As such you can have current through a conductor even if there
is no voltage difference across it!
On the other hand, if you claim there is indeed a different
voltage at the two ends of the conductor, then obviously
E is not 0 everywhere.
Your initial conditions violate E = - grad V.
- Randy
I would reconsider the answer to the question in
your place now.
LL
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| User: "" |
|
| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 05:25:02 PM |
|
|
xray4abc <lemhenyil@yahoo.ca> wrote:
Randy Poe wrote:
xray4abc wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
If E is zero everywhere inside the conductor, including where
it attaches to the source, then grad V is also zero. That is, there
is no voltage difference across the conductor and no current.
Sorry, you are wrong!
In a simple DC circuit where e= I(R+r), if you have R=0
you still get I= e/r , where r is the internal resistance/ impedance
of the DC source and "e" is the open circuit voltage of the source.
As such you can have current through a conductor even if there
is no voltage difference across it!
On the other hand, if you claim there is indeed a different
voltage at the two ends of the conductor, then obviously
E is not 0 everywhere.
Your initial conditions violate E = - grad V.
- Randy
I would reconsider the answer to the question in
your place now.
LL
If you want an answer in terms of voltage pushing current, it is the
voltage across the internal resistance of the source, just the same
as if the internal resistance were external and connected with ideal
wire.
--
Jim Pennino
Remove .spam.sux to reply.
.
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| User: "xray4abc" |
|
| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 06:59:19 PM |
|
|
wrote:
xray4abc <lemhenyil@yahoo.ca> wrote:
Randy Poe wrote:
xray4abc wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
If E is zero everywhere inside the conductor, including where
it attaches to the source, then grad V is also zero. That is, there
is no voltage difference across the conductor and no current.
Sorry, you are wrong!
In a simple DC circuit where e= I(R+r), if you have R=0
you still get I= e/r , where r is the internal resistance/ impedance
of the DC source and "e" is the open circuit voltage of the source.
As such you can have current through a conductor even if there
is no voltage difference across it!
On the other hand, if you claim there is indeed a different
voltage at the two ends of the conductor, then obviously
E is not 0 everywhere.
Your initial conditions violate E = - grad V.
- Randy
I would reconsider the answer to the question in
your place now.
LL
If you want an answer in terms of voltage pushing current, it is the
voltage across the internal resistance of the source, just the same
as if the internal resistance were external and connected with ideal
wire.
--
Jim Pennino
Remove .spam.sux to reply.
The issue is a lot more subtle than it appears to be.
The standard answer I was expecting could be something
referring to Poynting's vector though it would still be questionable.
LL
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| User: "" |
|
| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 08:05:03 PM |
|
|
xray4abc <lemhenyil@yahoo.ca> wrote:
jimp@specsol.spam.sux.com wrote:
xray4abc <lemhenyil@yahoo.ca> wrote:
Randy Poe wrote:
xray4abc wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
If E is zero everywhere inside the conductor, including where
it attaches to the source, then grad V is also zero. That is, there
is no voltage difference across the conductor and no current.
Sorry, you are wrong!
In a simple DC circuit where e= I(R+r), if you have R=0
you still get I= e/r , where r is the internal resistance/ impedance
of the DC source and "e" is the open circuit voltage of the source.
As such you can have current through a conductor even if there
is no voltage difference across it!
On the other hand, if you claim there is indeed a different
voltage at the two ends of the conductor, then obviously
E is not 0 everywhere.
Your initial conditions violate E = - grad V.
- Randy
I would reconsider the answer to the question in
your place now.
LL
If you want an answer in terms of voltage pushing current, it is the
voltage across the internal resistance of the source, just the same
as if the internal resistance were external and connected with ideal
wire.
--
Jim Pennino
Remove .spam.sux to reply.
The issue is a lot more subtle than it appears to be.
The standard answer I was expecting could be something
referring to Poynting's vector though it would still be questionable.
LL
Why would you expect that?
The problem is no different than what happens if you drop a big
screwdriver across the terminals of a real power supply.
--
Jim Pennino
Remove .spam.sux to reply.
.
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|
| User: "xray4abc" |
|
| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 10:20:15 PM |
|
|
wrote:
xray4abc <lemhenyil@yahoo.ca> wrote:
wrote:
xray4abc <lemhenyil@yahoo.ca> wrote:
Randy Poe wrote:
xray4abc wrote:
Consider an ideal metallic conductor, connected,
in a closed electrical circuit, to a non-ideal DC
power source.
E=0 inside the conductor; E and B are perpendicular
to the conductor outside the conductor and at its surface too.
What is, then, causing the electrical current through
the conductor? What is pushing the electrons along
the conductor?
If E is zero everywhere inside the conductor, including where
it attaches to the source, then grad V is also zero. That is, there
is no voltage difference across the conductor and no current.
Sorry, you are wrong!
In a simple DC circuit where e= I(R+r), if you have R=0
you still get I= e/r , where r is the internal resistance/ impedance
of the DC source and "e" is the open circuit voltage of the source.
As such you can have current through a conductor even if there
is no voltage difference across it!
On the other hand, if you claim there is indeed a different
voltage at the two ends of the conductor, then obviously
E is not 0 everywhere.
Your initial conditions violate E = - grad V.
- Randy
I would reconsider the answer to the question in
your place now.
LL
If you want an answer in terms of voltage pushing current, it is the
voltage across the internal resistance of the source, just the same
as if the internal resistance were external and connected with ideal
wire.
--
Jim Pennino
Remove .spam.sux to reply.
The issue is a lot more subtle than it appears to be.
The standard answer I was expecting could be something
referring to Poynting's vector though it would still be questionable.
LL
Why would you expect that?
The problem is no different than what happens if you drop a big
screwdriver across the terminals of a real power supply.
--
Jim Pennino
Remove .spam.sux to reply.
That's true.
Yet, still we did not answered the question.
If there is no electric field line(s) along the conductor or a
Lorentz force exerted INSIDE the conductor,
then how come that the electrons are drifting along the conductor ?
In order to sharpen the question, I have considered the case of
a zero resistance conductor.
In my opinion, it needs a little bit more than a traditional answer!
LL
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|
|
| User: "" |
|
| Title: Re: Simple electricity, and yet.....! |
15 Nov 2006 11:15:02 PM |
|
|
xray4abc <lemhenyil@yahoo.ca> wrote:
<snip>
That's true.
Yet, still we did not answered the question.
If there is no electric field line(s) along the conductor or a
Lorentz force exerted INSIDE the conductor,
then how come that the electrons are drifting along the conductor ?
In order to sharpen the question, I have considered the case of
a zero resistance conductor.
In my opinion, it needs a little bit more than a traditional answer!
LL
From a circuit analyses viewpoint, the answer is trivial.
What you are really asking is why and how does current flow in a conductor.
I don't see it being an ideal conductor makes any difference in the answer.
--
Jim Pennino
Remove .spam.sux to reply.
.
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|
|
| User: "xray4abc" |
|
| Title: Re: Simple electricity, and yet.....! |
16 Nov 2006 07:03:51 AM |
|
|
wrote:
xray4abc <lemhenyil@yahoo.ca> wrote:
<snip>
That's true.
Yet, still we did not answered the question.
If there is no electric field line(s) along the conductor or a
Lorentz force exerted INSIDE the conductor,
then how come that the electrons are drifting along the conductor ?
In order to sharpen the question, I have considered the case of
a zero resistance conductor.
In my opinion, it needs a little bit more than a traditional answer!
LL
From a circuit analyses viewpoint, the answer is trivial.
What you are really asking is why and how does current flow in a conductor.
Yes. I have always thought that the electric field created by
the power source was "pushing" the electrons.
It seems that there is something wrong with this picture of the
process.
I don't see it being an ideal conductor makes any difference in the answer.
Well, it helps, by simplifying the situation.
--
Jim Pennino
Remove .spam.sux to reply.
All the best,
LL
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|
| User: "Timo A. Nieminen" |
|
| Title: Re: Simple electricity, and yet.....! |
16 Nov 2006 01:48:10 PM |
|
|
On Thu, 16 Nov 2006, xray4abc wrote:
jimp@specsol.spam.sux.com wrote:
xray4abc <lemhenyil@yahoo.ca> wrote:
<snip>
That's true.
Yet, still we did not answered the question.
If there is no electric field line(s) along the conductor or a
Lorentz force exerted INSIDE the conductor,
then how come that the electrons are drifting along the conductor ?
In order to sharpen the question, I have considered the case of
a zero resistance conductor.
In my opinion, it needs a little bit more than a traditional answer!
LL
From a circuit analyses viewpoint, the answer is trivial.
What you are really asking is why and how does current flow in a conductor.
Yes. I have always thought that the electric field created by
the power source was "pushing" the electrons.
It seems that there is something wrong with this picture of the
process.
What makes aircraft fly at a constant velocity? Thrust = drag. What makes
a spaceship travel at constant velocity? Thrust = drag must still be true,
but drag = 0, therefore, one can conclude what?
You're specifically considering the case of R=0. Why should any force be
needed to keep the electrons moving?
From a circuit analysis viewpoint, it really is trivial. From a Maxwell
viewpoint, it's less trivial. If you want it to be an educational problem,
figure out how Maxwell gives you the circuit theory picture. Just keep in
mind that circuit theory general treats wires as R=0, while in Maxwell,
their conductivity is not infinite.
--
Timo Nieminen - Home page: http://www.physics.uq.edu.au/people/nieminen/
E-prints: http://eprint.uq.edu.au/view/person/Nieminen,_Timo_A..html
Shrine to Spirits: http://www.users.bigpond.com/timo_nieminen/spirits.html
.
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|
|
| User: "Sorcerer" |
|
| Title: Re: Simple electricity, and yet.....! |
16 Nov 2006 02:07:47 PM |
|
|
"Timo A. Nieminen" <timo@physics.uq.edu.au> wrote in message
news:Pine.WNT.4.64.0611170535280.716@serene.st...
| On Thu, 16 Nov 2006, xray4abc wrote:
|
| > wrote:
| >> xray4abc <lemhenyil@yahoo.ca> wrote:
| >>
| >> <snip>
| >>
| >>> That's true.
| >>> Yet, still we did not answered the question.
| >>> If there is no electric field line(s) along the conductor or a
| >>> Lorentz force exerted INSIDE the conductor,
| >>> then how come that the electrons are drifting along the conductor ?
| >>> In order to sharpen the question, I have considered the case of
| >>> a zero resistance conductor.
| >>> In my opinion, it needs a little bit more than a traditional answer!
| >>> LL
| >>
| >> From a circuit analyses viewpoint, the answer is trivial.
| >>
| >> What you are really asking is why and how does current flow in a
conductor.
| >
| > Yes. I have always thought that the electric field created by
| > the power source was "pushing" the electrons.
| > It seems that there is something wrong with this picture of the
| > process.
|
| What makes aircraft fly at a constant velocity? Thrust = drag. What makes
| a spaceship travel at constant velocity? Thrust = drag must still be true,
| but drag = 0, therefore, one can conclude what?
|
| You're specifically considering the case of R=0. Why should any force be
| needed to keep the electrons moving?
|
| From a circuit analysis viewpoint, it really is trivial. From a Maxwell
| viewpoint, it's less trivial. If you want it to be an educational problem,
| figure out how Maxwell gives you the circuit theory picture. Just keep in
| mind that circuit theory general treats wires as R=0, while in Maxwell,
| their conductivity is not infinite.
What limits the beam current in a CRT?
Thust equals drag?
Permittivity?
None of the above?
It really is trivial.
.
|
|
|
| User: "Timo Nieminen" |
|
| Title: Re: Simple electricity, and yet.....! |
16 Nov 2006 05:11:47 PM |
|
|
On Thu, 16 Nov 2006, Sorcerer wrote:
"Timo A. Nieminen" <timo@physics.uq.edu.au> wrote:
| On Thu, 16 Nov 2006, xray4abc wrote:
| >
| > Yes. I have always thought that the electric field created by
| > the power source was "pushing" the electrons.
| > It seems that there is something wrong with this picture of the
| > process.
|
| What makes aircraft fly at a constant velocity? Thrust = drag. What makes
| a spaceship travel at constant velocity? Thrust = drag must still be true,
| but drag = 0, therefore, one can conclude what?
|
| You're specifically considering the case of R=0. Why should any force be
| needed to keep the electrons moving?
|
| From a circuit analysis viewpoint, it really is trivial. From a Maxwell
| viewpoint, it's less trivial. If you want it to be an educational problem,
| figure out how Maxwell gives you the circuit theory picture. Just keep in
| mind that circuit theory general treats wires as R=0, while in Maxwell,
| their conductivity is not infinite.
What limits the beam current in a CRT?
Thust equals drag?
Permittivity?
None of the above?
It really is trivial.
What? You don't know the answer? You, the former "electronic engineer,
professionaly", need me to tell you? If you do know, are you so desperate
for attention that you're reduced to trolling on threads about circuit
theory?
It's essentially the same as the the PEC shorting a non-ideal power supply
as asked about by the OP: the current is mostly limited by the power
supply (in this case, the electron gun, its power supply etc). Do you
disagree that the total force on an electron moving at constant velocity
in a CRT is zero?
Despite the similarity between the CRT+circuit, and the PEC+circuit, there
is a fundamental difference: the charge density inside the PEC is zero,
while the charge density in the operating CRT is not, which will
contribute to limiting the current. Show your engineering talent: how
large is this contribution?
If you aren't just pointlessly trolled and really want to discuss physics,
you could continue some of our past discussions that you ran from:
Why do you claim that the field gradient is called the field strength?
What is the phase relationship (in time) between E and B in a
monochromatic plane-polarised plane EM wave in free space?
When is 5 hours earlier than 5 hours later than now?
Is the average magnitude of the velocity of an object that travels at
constant speed from A to B and back to A really equal to 0/0?
Why aren't you willing to discuss a derivation of the Lorentz
transformations?
http://groups.google.com.au/group/sci.physics/msg/07fbb2e45180a599?hl...
Why did you claim in successive posts that (a) Newton's laws don't hold in
any coordinate system, and (b) Newton's laws hold in every coordinate
system?
Now, from your past history, you'll either (a) cut and run,
(b) obsessively reply to my posts, or (c) respond with foul language.
Perhaps (d) all of the above, just as you did last time. The odds of you
actually making an attempt to discuss physics seems remote, from past
performance, but I ask: do you dare?
PS: Some might say that you are cowardly to post the type of
"content" that you post anonymously, but perhaps it is a sign of
consideration for your family, to protect them from being known as your
relatives - with all the associated stigma of possibly-hereditary
deficiency. You, such a sad and sorry example of a great and noble
people, indeed act in a compassionate manner to avoid your stink tainting
the reputation of that great and noble people!
PPS: Aren't I supposed to be a resident of your killfile?
--
Timo
.
|
|
|
| User: "Sorcerer" |
|
| Title: Re: Simple electricity, and yet.....! |
17 Nov 2006 12:18:38 AM |
|
|
"Timo Nieminen" <timo@physics.uq.edu.au> wrote in message
news:Pine.LNX.4.50.0611170852230.31514-100000@localhost...
| On Thu, 16 Nov 2006, Sorcerer wrote:
|
| > "Timo A. Nieminen" <timo@physics.uq.edu.au> wrote:
| > | On Thu, 16 Nov 2006, xray4abc wrote:
| > | >
| > | > Yes. I have always thought that the electric field created
by
| > | > the power source was "pushing" the electrons.
| > | > It seems that there is something wrong with this picture of the
| > | > process.
| > |
| > | What makes aircraft fly at a constant velocity? Thrust = drag. What
makes
| > | a spaceship travel at constant velocity? Thrust = drag must still be
true,
| > | but drag = 0, therefore, one can conclude what?
| > |
| > | You're specifically considering the case of R=0. Why should any force
be
| > | needed to keep the electrons moving?
| > |
| > | From a circuit analysis viewpoint, it really is trivial. From a
Maxwell
| > | viewpoint, it's less trivial. If you want it to be an educational
problem,
| > | figure out how Maxwell gives you the circuit theory picture. Just keep
in
| > | mind that circuit theory general treats wires as R=0, while in
Maxwell,
| > | their conductivity is not infinite.
| >
| > What limits the beam current in a CRT?
| > Thust equals drag?
| > Permittivity?
| > None of the above?
| > It really is trivial.
|
| What? You don't know the answer? You, the former "electronic engineer,
| professionaly", need me to tell you? If you do know, are you so desperate
| for attention that you're reduced to trolling on threads about circuit
| theory?
So Dork Van de merde found one typographical error and that's enough
to make me a troll?
| It's essentially the same as the the PEC shorting a non-ideal power supply
| as asked about by the OP: the current is mostly limited by the power
| supply (in this case, the electron gun, its power supply etc).
What? You don't know the the answer? You, the the so-called
"Ph.D. from the the Outback, unprofessionally", need me to tell you?
If you do know, are you so desperate for attention that you're reduced
to trolling on threads about typographical errors?
Limited by the electron gun... ridiculous.
I'm specifically considering the case of R=0.
You'll be saying lightning is limited by the the resistance of the the
lightning rod next. You are dumber than *****, Nieminen, and
YOU are the the troll. *****, you don't know the the answer
and you certainly don't understand circuit theory.
Androcles
.
|
|
|
| User: "Timo A. Nieminen" |
|
| Title: Re: Simple electricity, and yet.....! |
17 Nov 2006 06:09:43 PM |
|
|
On Fri, 17 Nov 2006, Sorcerer wrote:
"Timo Nieminen" <timo@physics.uq.edu.au> wrote:
| On Thu, 16 Nov 2006, Sorcerer wrote:
| > "Timo A. Nieminen" <timo@physics.uq.edu.au> wrote:
| > | On Thu, 16 Nov 2006, xray4abc wrote:
| > | >
| > | > Yes. I have always thought that the electric field created
by
| > | > the power source was "pushing" the electrons.
| > | > It seems that there is something wrong with this picture of the
| > | > process.
| > |
| > | What makes aircraft fly at a constant velocity? Thrust = drag. What
makes
| > | a spaceship travel at constant velocity? Thrust = drag must still be
true,
| > | but drag = 0, therefore, one can conclude what?
| > |
| > | You're specifically considering the case of R=0. Why should any force
be
| > | needed to keep the electrons moving?
| > |
| > | From a circuit analysis viewpoint, it really is trivial. From a
Maxwell
| > | viewpoint, it's less trivial. If you want it to be an educational
problem,
| > | figure out how Maxwell gives you the circuit theory picture. Just keep
in
| > | mind that circuit theory general treats wires as R=0, while in
Maxwell,
| > | their conductivity is not infinite.
| >
| > What limits the beam current in a CRT?
| > Thust equals drag?
| > Permittivity?
| > None of the above?
| > It really is trivial.
|
| What? You don't know the answer? You, the former "electronic engineer,
| professionaly", need me to tell you? If you do know, are you so desperate
| for attention that you're reduced to trolling on threads about circuit
| theory?
So Dork Van de merde found one typographical error and that's enough
to make me a troll?
Not at all. Is your comprehension of written English so poor? Why don't
you go back and actually read what I wrote?
In any case, I note a complete lack of further explanation on your part,
apart from a denial that what limits the beam current has anything to do
with the electron gun, it's power supply, etc. What, do you think that
something to do with the empty space in the CRT limits the current?
| It's essentially the same as the the PEC shorting a non-ideal power supply
| as asked about by the OP: the current is mostly limited by the power
| supply (in this case, the electron gun, its power supply etc).
What? You don't know the the answer? You, the the so-called
"Ph.D. from the the Outback, unprofessionally", need me to tell you?
If you do know, are you so desperate for attention that you're reduced
to trolling on threads about typographical errors?
Oh, are you learning to ape your betters? Well, maybe one day, you'll be
able to pas a Turing test if continue to do so.
Limited by the electron gun... ridiculous.
I'm specifically considering the case of R=0.
R=0 of what? To be relevant to the thread, you'd be considering the case
of the empty space having R=0, and if so, why would something other than
the driving circuit limit the current? Or do you think the empty space has
properties that limit the current?
You'll be saying lightning is limited by the the resistance of the the
lightning rod next. You are dumber than *****, Nieminen, and
YOU are the the troll. *****, you don't know the the answer
and you certainly don't understand circuit theory.
Oh, and you cut a large portion of my reply. It appears that you are both
a cowardly hypocrite and a hypocritical coward, given your loud bleating
about the evils of snipping! Are you going to claim that the correct
answer to your CRT question is the part of my reply that you cut without
reply? Do tell us, if you have any professional credibility, what limits
the current in the electron beam in a CRT, other than the electron gun and
the attached circuitry and any space charge effects!
Well, google easily reveals your reluctance to actually discuss physics,
your general posting habits, and so on, so I don't expect any reply on
this point.
I'll give a chance to redeem yourself, and actually discuss some physics,
by taking up some of the items you've refused to discuss in the past:
Why do you claim that the field gradient is called the field strength?
What is the phase relationship (in time) between E and B in a
monochromatic plane-polarised plane EM wave in free space?
When is 5 hours earlier than 5 hours later than now?
Is the average magnitude of the velocity of an object that travels at
constant speed from A to B and back to A really equal to 0/0?
Why aren't you willing to discuss a derivation of the Lorentz
transformations?
http://groups.google.com.au/group/sci.physics/msg/07fbb2e45180a599?hl...
Why did you claim in successive posts that (a) Newton's laws don't hold in
any coordinate system, and (b) Newton's laws hold in every coordinate
system?
Now, from your past history, you'll either (a) cut and run,
(b) obsessively reply to my posts, or (c) respond with foul language.
Perhaps (d) all of the above, just as you did last time. The odds of you
actually making an attempt to discuss physics seems remote, from past
performance, but I ask: do you dare?
PS: Some might say that you are cowardly to post the type of
"content" that you post anonymously, but perhaps it is a sign of
consideration for your family, to protect them from being known as your
relatives - with all the associated stigma of possibly-hereditary
deficiency. You, such a sad and sorry example of a great and noble
people, indeed act in a compassionate manner to avoid your stink tainting
the reputation of that great and noble people!
PPS: Aren't I supposed to be a resident of your killfile?
--
Timo
.
|
|
|
| User: "Sorcerer" |
|
| Title: Re: Simple electricity, and yet.....! |
18 Nov 2006 12:46:09 AM |
|
|
"Timo A. Nieminen" <timo@physics.uq.edu.au> wrote in message
news:Pine.WNT.4.64.0611180955001.1132@serene.st...
| On Fri, 17 Nov 2006, Sorcerer wrote:
|
| > "Timo Nieminen" <timo@physics.uq.edu.au> wrote:
| > | On Thu, 16 Nov 2006, Sorcerer wrote:
| > | > "Timo A. Nieminen" <timo@physics.uq.edu.au> wrote:
| > | > | On Thu, 16 Nov 2006, xray4abc wrote:
| > | > | >
| > | > | > Yes. I have always thought that the electric field
created
| > by
| > | > | > the power source was "pushing" the electrons.
| > | > | > It seems that there is something wrong with this picture of the
| > | > | > process.
| > | > |
| > | > | What makes aircraft fly at a constant velocity? Thrust = drag.
What
| > makes
| > | > | a spaceship travel at constant velocity? Thrust = drag must still
be
| > true,
| > | > | but drag = 0, therefore, one can conclude what?
| > | > |
| > | > | You're specifically considering the case of R=0. Why should any
force
| > be
| > | > | needed to keep the electrons moving?
| > | > |
| > | > | From a circuit analysis viewpoint, it really is trivial. From a
| > Maxwell
| > | > | viewpoint, it's less trivial. If you want it to be an educational
| > problem,
| > | > | figure out how Maxwell gives you the circuit theory picture. Just
keep
| > in
| > | > | mind that circuit theory general treats wires as R=0, while in
| > Maxwell,
| > | > | their conductivity is not infinite.
| > | >
| > | > What limits the beam current in a CRT?
| > | > Thust equals drag?
| > | > Permittivity?
| > | > None of the above?
| > | > It really is trivial.
| > |
| > | What? You don't know the answer? You, the former "electronic engineer,
| > | professionaly", need me to tell you? If you do know, are you so
desperate
| > | for attention that you're reduced to trolling on threads about circuit
| > | theory?
| >
| > So Dork Van de merde found one typographical error and that's enough
| > to make me a troll?
|
| Not at all. Is your comprehension of written English so poor?
I can clearly see YOUR English is so poor YOU cannot spell
"professionally", then.
| Why don't
| you go back and actually read what I wrote?
I did, you mispelt "professionally" and failed to answer my question, troll.
| In any case, I note a complete lack of further explanation on your part,
| apart from a denial that what limits the beam current has anything to do
| with the electron gun, it's power supply, etc. What, do you think that
| something to do with the empty space in the CRT limits the current?
From a circuit analysis viewpoint, it really is trivial. What, do you think
that
something to do with the empty space in the CRT limits the current?
Why don't you go back and actually read what I wrote? Never mind, I know
why.
|
| > | It's essentially the same as the the PEC shorting a non-ideal power
supply
| > | as asked about by the OP: the current is mostly limited by the power
| > | supply (in this case, the electron gun, its power supply etc).
| >
| > What? You don't know the the answer? You, the the so-called
| > "Ph.D. from the the Outback, unprofessionally", need me to tell you?
| > If you do know, are you so desperate for attention that you're reduced
| > to trolling on threads about typographical errors?
|
| Oh, are you learning to ape your betters?
You? "Better"? No, *****, I'm adept in shoving your own arrogant
ignorance back up your arse.
Well, maybe one day, you'll be
| able to pas a Turing test if continue to do so.
pas?
Is that how you 'professionaly' spell "past", "pass", "phase", or you've
lapsed into French, what?
Maybe one day in the distant future I'll believe you are artificially
intelligent. Hmm... On second thoughts, I'll be dead first.
|
| > Limited by the electron gun... ridiculous.
| > I'm specifically considering the case of R=0.
|
| R=0 of what?
Ohms, moron. Do I have to explain R is resistance and has units of ohms?
| To be relevant to the thread, you'd be considering the case
| of the empty space having R=0, and if so, why would something other than
| the driving circuit limit the current? Or do you think the empty space has
| properties that limit the current?
Whine, whine, whine, troll, troll, troll.
So we can agree that empty space has undefined conductance.
Now, how about passing the Turing test and answering MY question, *****?
What limits the beam current in a CRT? Permittivity?
| > You'll be saying lightning is limited by the the resistance of the the
| > lightning rod next. You are dumber than *****, Nieminen, and
| > YOU are the the troll. *****, you don't know the the answer
| > and you certainly don't understand circuit theory.
|
| Oh, and you cut a large portion of my reply.
Refusal to discuss physics noted.
I'm doing it again, too, since it doesn't answer my question.
We'll get to your questions after you answer mine.
Does permittivity limit the beam current in a CRT, ranting troll?
Androcles
.
|
|
|
| User: "Timo A. Nieminen" |
|
| Title: Re: Simple electricity, and yet.....! |
18 Nov 2006 04:14:01 AM |
|
|
On Sat, 18 Nov 2006, Sorcerer wrote:
"Timo A. Nieminen" <timo@physics.uq.edu.au> wrote:
| On Fri, 17 Nov 2006, Sorcerer wrote:
| > "Timo Nieminen" <timo@physics.uq.edu.au> wrote:
| > | On Thu, 16 Nov 2006, Sorcerer wrote:
| > | > "Timo A. Nieminen" <timo@physics.uq.edu.au> wrote:
| > | > | On Thu, 16 Nov 2006, xray4abc wrote:
| > | > | >
| > | > | > Yes. I have always thought that the electric field
created
| > by
| > | > | > the power source was "pushing" the electrons.
| > | > | > It seems that there is something wrong with this picture of the
| > | > | > process.
| > | > |
| > | > | What makes aircraft fly at a constant velocity? Thrust = drag.
What
| > makes
| > | > | a spaceship travel at constant velocity? Thrust = drag must still
be
| > true,
| > | > | but drag = 0, therefore, one can conclude what?
| > | > |
| > | > | You're specifically considering the case of R=0. Why should any
force
| > be
| > | > | needed to keep the electrons moving?
| > | > |
| > | > | From a circuit analysis viewpoint, it really is trivial. From a
| > Maxwell
| > | > | viewpoint, it's less trivial. If you want it to be an educational
| > problem,
| > | > | figure out how Maxwell gives you the circuit theory picture. Just
keep
| > in
| > | > | mind that circuit theory general treats wires as R=0, while in
| > Maxwell,
| > | > | their conductivity is not infinite.
| > | >
| > | > What limits the beam current in a CRT?
| > | > Thust equals drag?
| > | > Permittivity?
| > | > None of the above?
| > | > It really is trivial.
| > |
| > | What? You don't know the answer? You, the former "electronic engineer,
| > | professionaly", need me to tell you? If you do know, are you so
desperate
| > | for attention that you're reduced to trolling on threads about circuit
| > | theory?
| >
| > So Dork Van de merde found one typographical error and that's enough
| > to make me a troll?
|
| Not at all. Is your comprehension of written English so poor?
I can clearly see YOUR English is so poor YOU cannot spell
"professionally", then.
Oh? You're complaining about my quoting of your spelling? Do you have so
little of substance to post about that you're spell-flaming your own
postings?
| Why don't
| you go back and actually read what I wrote?
I did, you mispelt "professionally" and failed to answer my question, troll.
Oh? You're complaining about my quoting of your spelling? Do you have so
little of substance to post about that you're spell-flaming your own
postings?
| In any case, I note a complete lack of further explanation on your part,
| apart from a denial that what limits the beam current has anything to do
| with the electron gun, it's power supply, etc. What, do you think that
| something to do with the empty space in the CRT limits the current?
From a circuit analysis viewpoint, it really is trivial. What, do you think
that
something to do with the empty space in the CRT limits the current?
Why don't you go back and actually read what I wrote? Never mind, I know
why.
What, you have reply of any substance? All you can do is echo my original
question? Hi, Eliza!
| > | It's essentially the same as the the PEC shorting a non-ideal power
supply
| > | as asked about by the OP: the current is mostly limited by the power
| > | supply (in this case, the electron gun, its power supply etc).
| >
| > What? You don't know the the answer? You, the the so-called
| > "Ph.D. from the the Outback, unprofessionally", need me to tell you?
| > If you do know, are you so desperate for attention that you're reduced
| > to trolling on threads about typographical errors?
|
| Oh, are you learning to ape your betters?
You? "Better"? No, *****, I'm adept in shoving your own arrogant
ignorance back up your arse.
Hi, Eliza!
Well, maybe one day, you'll be
| able to pas a Turing test if continue to do so.
pas?
Hi, Eliza!
Is that how you 'professionaly' spell "past", "pass", "phase", or you've
lapsed into French, what?
Maybe one day in the distant future I'll believe you are artificially
intelligent. Hmm... On second thoughts, I'll be dead first.
Hi, Eliza!
| > Limited by the electron gun... ridiculous.
| > I'm specifically considering the case of R=0.
|
| R=0 of what?
Ohms, moron. Do I have to explain R is resistance and has units of ohms?
Oh, you're not willing to say what has R=0? Why not?
| To be relevant to the thread, you'd be considering the case
| of the empty space having R=0, and if so, why would something other than
| the driving circuit limit the current? Or do you think the empty space has
| properties that limit the current?
Whine, whine, whine, troll, troll, troll.
So we can agree that empty space has undefined conductance.
Now, how about passing the Turing test and answering MY question, *****?
What limits the beam current in a CRT? Permittivity?
I've already answered that. You cut half the reply, being the POS you are.
Don't you know the answer, being the oh-so-wonderful "electronic
engineer" you are (or were)?
| > You'll be saying lightning is limited by the the resistance of the the
| > lightning rod next. You are dumber than *****, Nieminen, and
| > YOU are the the troll. *****, you don't know the the answer
| > and you certainly don't understand circuit theory.
|
| Oh, and you cut a large portion of my reply.
Refusal to discuss physics noted.
Oh, you note your own refusal to discuss physics? Well, hardly a surprise,
being that you're well known to be as useful to discuss physics with as a
piece of dogshit on the street. I also note your copying of my own
wording. At least you either have the wit to ape your betters, or: Hi,
Eliza!
I'm doing it again, too, since it doesn't answer my question.
We'll get to your questions after you answer mine.
Does permittivity limit the beam current in a CRT, ranting troll?
The questions you ask have been answered, all questions asked of you are
cut, you cowardly POS, shitty hypocritical coward, cowardly hypocrite,
etc.
Well, google easily reveals your reluctance to actually discuss physics,
your general posting habits, and so on, so I don't expect any reply on
this point.
I'll give a chance to redeem yourself, and actually discuss some physics,
by taking up some of the items you've refused to discuss in the past:
Why do you claim that the field gradient is called the field strength?
What is the phase relationship (in time) between E and B in a
monochromatic plane-polarised plane EM wave in free space?
When is 5 hours earlier than 5 hours later than now?
Is the average magnitude of the velocity of an object that travels at
constant speed from A to B and back to A really equal to 0/0?
Why aren't you willing to discuss a derivation of the Lorentz
transformations?
http://groups.google.com.au/group/sci.physics/msg/07fbb2e45180a599?hl...
Why did you claim in successive posts that (a) Newton's laws don't hold in
any coordinate system, and (b) Newton's laws hold in every coordinate
system?
Now, from your past history, you'll either (a) cut and run,
(b) obsessively reply to my posts, or (c) respond with foul language.
Perhaps (d) all of the above, just as you did last time. The odds of you
actually making an attempt to discuss physics seems remote, from past
performance, but I ask: do you dare?
PS: Some might say that you are cowardly to post the type of
"content" that you post anonymously, but perhaps it is a sign of
consideration for your family, to protect them from being known as your
relatives - with all the associated stigma of possibly-hereditary
deficiency. You, such a sad and sorry example of a great and noble
people, indeed act in a compassionate manner to avoid your stink tainting
the reputation of that great and noble people!
PPS: Aren't I supposed to be a resident of your killfile?
--
Timo
.
|
|
|
| User: "Sorcerer" |
|
| Title: Re: Simple electricity, and yet.....! |
18 Nov 2006 07:11:08 AM |
|
|
"Timo A. Nieminen" <timo@physics.uq.edu.au> wrote in message
news:Pine.WNT.4.64.0611181959480.1440@serene.st...
| On Sat, 18 Nov 2006, Sorcerer wrote:
|
| > "Timo A. Nieminen" <timo@physics.uq.edu.au> wrote:
| > | On Fri, 17 Nov 2006, Sorcerer wrote:
| > | > "Timo Nieminen" <timo@physics.uq.edu.au> wrote:
| > | > | On Thu, 16 Nov 2006, Sorcerer wrote:
| > | > | > "Timo A. Nieminen" <timo@physics.uq.edu.au> wrote:
| > | > | > | On Thu, 16 Nov 2006, xray4abc wrote:
| > | > | > | >
| > | > | > | > Yes. I have always thought that the electric field
| > created
| > | > by
| > | > | > | > the power source was "pushing" the electrons.
| > | > | > | > It seems that there is something wrong with this picture of
the
| > | > | > | > process.
| > | > | > |
| > | > | > | What makes aircraft fly at a constant velocity? Thrust = drag.
| > What
| > | > makes
| > | > | > | a spaceship travel at constant velocity? Thrust = drag must
still
| > be
| > | > true,
| > | > | > | but drag = 0, therefore, one can conclude what?
| > | > | > |
| > | > | > | You're specifically considering the case of R=0. Why should
any
| > force
| > | > be
| > | > | > | needed to keep the electrons moving?
| > | > | > |
| > | > | > | From a circuit analysis viewpoint, it really is trivial. From
a
| > | > Maxwell
| > | > | > | viewpoint, it's less trivial. If you want it to be an
educational
| > | > problem,
| > | > | > | figure out how Maxwell gives you the circuit theory picture.
Just
| > keep
| > | > in
| > | > | > | mind that circuit theory general treats wires as R=0, while in
| > | > Maxwell,
| > | > | > | their conductivity is not infinite.
| > | > | >
| > | > | > What limits the beam current in a CRT?
| > | > | > Thust equals drag?
| > | > | > Permittivity?
| > | > | > None of the above?
| > | > | > It really is trivial.
| > | > |
| > | > | What? You don't know the answer? You, the former "electronic
engineer,
| > | > | professionaly", need me to tell you? If you do know, are you so
| > desperate
| > | > | for attention that you're reduced to trolling on threads about
circuit
| > | > | theory?
| > | >
| > | > So Dork Van de merde found one typographical error and that's enough
| > | > to make me a troll?
| > |
| > | Not at all. Is your comprehension of written English so poor?
| >
| > I can clearly see YOUR English is so poor YOU cannot spell
| > "professionally", then.
|
| Oh?
Refusal to discuss physics noted.
I don't know the answer to "Oh?", what is it?
| You're complaining about my quoting of your spelling?
Refusal to discuss physics noted.
No, I'm pointing out your error for you to correct.
| Do you have so
| little of substance to post about that you're spell-flaming your own
| postings?
Refusal to discuss physics noted.
|
| > | Why don't
| > | you go back and actually read what I wrote?
| >
| > I did, you mispelt "professionally" and failed to answer my question,
troll.
|
| Oh?
Refusal to discuss physics noted.
I don't know the answer to "Oh?", what is it?
| You're complaining about my quoting of your spelling?
Refusal to discuss physics noted.
| Do you have so
| little of substance to post about that you're spell-flaming your own
| postings?
Refusal to discuss physics noted.
|
| > | In any case, I note a complete lack of further explanation on your
part,
| > | apart from a denial that what limits the beam current has anything to
do
| > | with the electron gun, it's power supply, etc. What, do you think that
| > | something to do with the empty space in the CRT limits the current?
| >
| > From a circuit analysis viewpoint, it really is trivial. What, do you
think
| > that
| > something to do with the empty space in the CRT limits the current?
| > Why don't you go back and actually read what I wrote? Never mind, I know
| > why.
|
| What, you have reply of any substance?
Why don't you go back and actually read what I wrote? Never mind, I know
why.
| All you can do is echo my original
| question?
People who live in glass houses...
| Hi, Eliza!
Hi Henry, there's a hole on your bucket, child.
http://en.wikipedia.org/wiki/There's_a_Hole_in_My_Bucket
| > | > | It's essentially the same as the the PEC shorting a non-ideal
power
| > supply
| > | > | as asked about by the OP: the current is mostly limited by the
power
| > | > | supply (in this case, the electron gun, its power supply etc).
| > | >
| > | > What? You don't know the the answer? You, the the so-called
| > | > "Ph.D. from the the Outback, unprofessionally", need me to tell
you?
| > | > If you do know, are you so desperate for attention that you're
reduced
| > | > to trolling on threads about typographical errors?
| > |
| > | Oh, are you learning to ape your betters?
| >
| > You? "Better"? No, *****, I'm adept in shoving your own arrogant
| > ignorance back up your arse.
|
| Hi, Eliza!
Hi Henry, then mend it.
|
| > Well, maybe one day, you'll be
| > | able to pas a Turing test if continue to do so.
| >
| > pas?
|
| Hi, Eliza!
Note: the knuckle-dragging Neanderthal "Timo A. Nieminen" has
passed the Turing test for the species "gorrilla gorrilla". It has failed
the Turing test for homo sapiens, it is unable to answer a question
and has gone into repetition mode.
| > Is that how you 'professionaly' spell "past", "pass", "phase", or you've
| > lapsed into French, what?
| > Maybe one day in the distant future I'll believe you are artificially
| > intelligent. Hmm... On second thoughts, I'll be dead first.
|
| Hi, Eliza!
Turing test terminated early, subject deranged. Results recorded at:
http://www.androcles01.pwp.blueyonder.co.uk/TrollExample.htm
.
|
|
|
| User: "Timo A. Nieminen" |
|
| Title: Re: Simple electricity, and yet.....! |
18 Nov 2006 01:15:38 PM |
|
|
On Sat, 18 Nov 2006, Sorcerer wrote:
Refusal to discuss physics noted.
Are you merely an example of artifical stupidity?
On the positive side, you're learning to copy some of my words. Young
children will do this kind of thing, copy without understanding, and
eventually they begin to understand. There is hope for you! You have
advanced to the level of a 3 year old! Keep it up!
Why do you highlight your own refusal to discuss physics? Why do you keep
cutting all the questions of physics? The questions you asked have been
answered, all questions asked of you are cut. It's very clear who refuses
to discuss physics. You are very adept at making it clear that you are a
cowardly POS, shitty hypocritical coward, cowardly hypocrite, etc.
Well, google easily reveals your reluctance to actually discuss physics,
your general posting habits, and so on, so I don't expect any reply on
this point.
I'll give a chance to redeem yourself, and actually discuss some physics,
by taking up some of the items you've refused to discuss in the past:
What limits the beam current in a CRT?
Why do you claim that the field gradient is called the field strength?
What is the phase relationship (in time) between E and B in a
monochromatic plane-polarised plane EM wave in free space?
When is 5 hours earlier than 5 hours later than now?
Is the average magnitude of the velocity of an object that travels at
constant speed from A to B and back to A really equal to 0/0?
Why aren't you willing to discuss a derivation of the Lorentz
transformations?
http://groups.google.com.au/group/sci.physics/msg/07fbb2e45180a599?hl...
Why did you claim in successive posts that (a) Newton's laws don't hold in
any coordinate system, and (b) Newton's laws hold in every coordinate
system?
Now, from your past history, you'll either (a) cut and run,
(b) obsessively reply to my posts, or (c) respond with foul language.
Perhaps (d) all of the above, just as you did last time. The odds of you
actually making an attempt to discuss physics seems remote, from past
performance, but I ask: do you dare?
PS: Some might say that you are cowardly to post the type of
"content" that you post anonymously, but perhaps it is a sign of
consideration for your family, to protect them from being known as your
relatives - with all the associated stigma of possibly-hereditary
deficiency. You, such a sad and sorry example of a great and noble
people, indeed act in a compassionate manner to avoid your stink tainting
the reputation of that great and noble people!
PPS: Aren't I supposed to be a resident of your killfile?
--
Timo
.
|
|
|
| User: "Sorcerer" |
|
| Title: Re: Simple electricity, and yet.....! |
18 Nov 2006 04:14:48 PM |
|
|
"Timo A. Nieminen" <timo@physics.uq.edu.au> wrote in message
news:Pine.WNT.4.64.0611190507060.524@serene.st...
| On Sat, 18 Nov 2006, Sorcerer wrote:
|
| > Refusal to discuss physics noted.
[snip]
*****, *****, experiment over.
http://www.androcles01.pwp.blueyonder.co.uk/TrollExample.htm
.
|
|
|
| User: "Dirk Van de moortel" |
|
| Title: Re: Simple electricity, and yet.....! |
18 Nov 2006 04:48:58 PM |
|
|
"Sorcerer" <Headmaster@hogwarts.physics_e> wrote in message news:sBL7h.150551$3x1.36821@fe1.news.blueyonder.co.uk...
"Timo A. Nieminen" <timo@physics.uq.edu.au> wrote in message
news:Pine.WNT.4.64.0611190507060.524@serene.st...
| On Sat, 18 Nov 2006, Sorcerer wrote:
|
| > Refusal to discuss physics noted.
[snip]
*****, *****, experiment over.
http://www.androcles01.pwp.blueyonder.co.uk/TrollExample.htm
Hey Timo, it seems he took options (a) and (c).
Good job ;-)
Dirk Vdm
.
|
|
|
| User: "Timo A. Nieminen" |
|
| Title: Re: Simple electricity, and yet.....! |
19 Nov 2006 02:30:41 AM |
|
|
On Sat, 18 Nov 2006, Dirk Van de moortel wrote:
"Sorcerer" <Headmaster@hogwarts.physics_e> wrote in message news:sBL7h.150551$3x1.36821@fe1.news.blueyonder.co.uk...
"Timo A. Nieminen" <timo@physics.uq.edu.au> wrote in message
news:Pine.WNT.4.64.0611190507060.524@serene.st...
| On Sat, 18 Nov 2006, Sorcerer wrote:
|
| > Refusal to discuss physics noted.
[snip]
*****, *****, experiment over.
http://www.androcles01.pwp.blueyonder.co.uk/TrollExample.htm
Hey Timo, it seems he took options (a) and (c).
Good job ;-)
Eliza is predictable!
--
Timo Nieminen - Home page: http://www.physics.uq.edu.au/people/nieminen/
E-prints: http://eprint.uq.edu.au/view/person/Nieminen,_Timo_A..html
Shrine to Spirits: http://www.users.bigpond.com/timo_nieminen/spirits.html
.
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