Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[mixent]

In reply to  Harry Veeder's message of Thu, 15 Oct 2009 23:59:56 -0400:
Hi,
[snip]

Well Harry, I've done my best. I have nothing more to contribute.
>
>
>- Original Message -
>From: mix...@bigpond.com
>Date: Tuesday, October 13, 2009 5:28 pm
>Subject: Re: correction /Re: [Vo]:The Electric Field Outside a
>Stationary Resistive Wire Carrying a Constant Current
>
>> In reply to  Harry Veeder's message of Mon, 12 Oct 2009 02:35:43 -
>> 0400:Hi,
>> >Ok, I guess it is necessary to distinguish between a capacitor, a
>> >battery and an EMF.  Both a battery and a capacitor can produce a
>> >current for a _limited_ period of time, whereas an EMF can produce a
>> >current for an _unlimited_ period of time. 
>> 
>> There ain't no sich animal. Nothing runs forever. The universe is a 
>> big battery,
>> and it's running down. 
>
>Who can say for sure? 
>Who wants to say for sure? 
>IMO, the application of some currently recognized physical principles
>governing machines to the entire universe is like painting oneself into
>a (spiritual) corner. Newton was aware his clockwork universe would run down
>so he allowed God to periodically intervene in his clockwork universe to
>wind things up. On a deeper level he believed creation was more than
>what could be explained by his axioms/laws. 
>
>> You can only maintain an EMF at a "constant" 
>> level, when
>> current is flowing in a resistive circuit, by supplying energy
>> IOW you have to
>> "pump" the electrons from the low voltage side back to the high 
>> voltage side.
>> This is usually done with a changing magnetic field (i.e. a 
>> generator or
>> dynamo), which once again introduces a step in the voltage going 
>> around the
>> circuit. You can picture the voltage at each point as single 
>> rotation of a helix
>> with a vertical axis with the begin and end points joined by a 
>> straight vertical
>> line. That vertical line is where the energy is added. Energy is 
>> lost to
>> resistance as the current runs around the helix.
>
>I agree.
>The point I have been trying to make is that an EMF is technically not
>same thing as electrical field. They are different animals.
>
>> >
>> >With that in mind, let me refine the question. Can a current which 
>> runs>indefinitely (and does not occur in a superconductor) be 
>> explained>consistently only with the concept of an electric field?
>> [snip]
>> Regards,
>> 
>> Robin van Spaandonk
>> 
>> http://rvanspaa.freehostia.com/Project.html
>> 
>
>
>Harry
Regards,

Robin van Spaandonk

http://rvanspaa.freehostia.com/Project.html

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[Harry Veeder]

- Original Message -
From: mix...@bigpond.com
Date: Tuesday, October 13, 2009 5:28 pm
Subject: Re: correction /Re: [Vo]:The Electric Field Outside a
Stationary Resistive Wire Carrying a Constant Current

> In reply to  Harry Veeder's message of Mon, 12 Oct 2009 02:35:43 -
> 0400:Hi,
> >Ok, I guess it is necessary to distinguish between a capacitor, a
> >battery and an EMF.  Both a battery and a capacitor can produce a
> >current for a _limited_ period of time, whereas an EMF can produce a
> >current for an _unlimited_ period of time. 
> 
> There ain't no sich animal. Nothing runs forever. The universe is a 
> big battery,
> and it's running down. 

Who can say for sure? 
Who wants to say for sure? 
IMO, the application of some currently recognized physical principles
governing machines to the entire universe is like painting oneself into
a (spiritual) corner. Newton was aware his clockwork universe would run down
so he allowed God to periodically intervene in his clockwork universe to
wind things up. On a deeper level he believed creation was more than
what could be explained by his axioms/laws. 

> You can only maintain an EMF at a "constant" 
> level, when
> current is flowing in a resistive circuit, by supplying energy
> IOW you have to
> "pump" the electrons from the low voltage side back to the high 
> voltage side.
> This is usually done with a changing magnetic field (i.e. a 
> generator or
> dynamo), which once again introduces a step in the voltage going 
> around the
> circuit. You can picture the voltage at each point as single 
> rotation of a helix
> with a vertical axis with the begin and end points joined by a 
> straight vertical
> line. That vertical line is where the energy is added. Energy is 
> lost to
> resistance as the current runs around the helix.

I agree.
The point I have been trying to make is that an EMF is technically not
same thing as electrical field. They are different animals.

> >
> >With that in mind, let me refine the question. Can a current which 
> runs>indefinitely (and does not occur in a superconductor) be 
> explained>consistently only with the concept of an electric field?
> [snip]
> Regards,
> 
> Robin van Spaandonk
> 
> http://rvanspaa.freehostia.com/Project.html
> 


Harry

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[Abd ul-Rahman Lomax]

At 06:20 PM 10/13/2009, Ron Wormus wrote:

This link is for Harry;

Physicists Measure Elusive 'Persistent Current' That Flows Forever



Doesn't sound like anything is ever going to be powered by it.
Ron


Yeah. "Persistent Current" sounds like DC to me, but this apparently 
is AC. Or is it?


This seems to be a copy of the actual paper: 
http://arxiv.org/ftp/arxiv/papers/0906/0906.4780.pdf


Or is it this:
http://arxiv.org/PS_cache/arxiv/pdf/0810/0810.4384v2.pdf

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[Ron Wormus]

This link is for Harry;

Physicists Measure Elusive 'Persistent Current' That Flows Forever



Doesn't sound like anything is ever going to be powered by it.
Ron

--On Wednesday, October 14, 2009 8:28 AM +1100 mix...@bigpond.com wrote:


In reply to  Harry Veeder's message of Mon, 12 Oct 2009 02:35:43 -0400:
Hi,

Ok, I guess it is necessary to distinguish between a capacitor, a
battery and an EMF.  Both a battery and a capacitor can produce a
current for a _limited_ period of time, whereas an EMF can produce a
current for an _unlimited_ period of time.


There ain't no sich animal. Nothing runs forever. The universe is a big battery,
and it's running down. You can only maintain an EMF at a "constant" level, when
current is flowing in a resistive circuit, by supplying energy. IOW you have to
"pump" the electrons from the low voltage side back to the high voltage side.
This is usually done with a changing magnetic field (i.e. a generator or
dynamo), which once again introduces a step in the voltage going around the
circuit. You can picture the voltage at each point as single rotation of a helix
with a vertical axis with the begin and end points joined by a straight vertical
line. That vertical line is where the energy is added. Energy is lost to
resistance as the current runs around the helix.



With that in mind, let me refine the question. Can a current which runs
indefinitely (and does not occur in a superconductor) be explained
consistently only with the concept of an electric field?

[snip]
Regards,

Robin van Spaandonk

http://rvanspaa.freehostia.com/Project.html

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[mixent]

In reply to  Harry Veeder's message of Mon, 12 Oct 2009 02:35:43 -0400:
Hi,
>Ok, I guess it is necessary to distinguish between a capacitor, a
>battery and an EMF.  Both a battery and a capacitor can produce a
>current for a _limited_ period of time, whereas an EMF can produce a
>current for an _unlimited_ period of time. 

There ain't no sich animal. Nothing runs forever. The universe is a big battery,
and it's running down. You can only maintain an EMF at a "constant" level, when
current is flowing in a resistive circuit, by supplying energy. IOW you have to
"pump" the electrons from the low voltage side back to the high voltage side.
This is usually done with a changing magnetic field (i.e. a generator or
dynamo), which once again introduces a step in the voltage going around the
circuit. You can picture the voltage at each point as single rotation of a helix
with a vertical axis with the begin and end points joined by a straight vertical
line. That vertical line is where the energy is added. Energy is lost to
resistance as the current runs around the helix.

>
>With that in mind, let me refine the question. Can a current which runs
>indefinitely (and does not occur in a superconductor) be explained
>consistently only with the concept of an electric field?
[snip]
Regards,

Robin van Spaandonk

http://rvanspaa.freehostia.com/Project.html

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[Harry Veeder]

Ok, I guess it is necessary to distinguish between a capacitor, a
battery and an EMF.  Both a battery and a capacitor can produce a
current for a _limited_ period of time, whereas an EMF can produce a
current for an _unlimited_ period of time. 

With that in mind, let me refine the question. Can a current which runs
indefinitely (and does not occur in a superconductor) be explained
consistently only with the concept of an electric field?

harry 

- Original Message -
From: mix...@bigpond.com
Date: Sunday, October 11, 2009 5:03 pm
Subject: Re: correction /Re: [Vo]:The Electric Field Outside a
Stationary Resistive Wire Carrying a Constant Current

> In reply to  Harry Veeder's message of Thu, 08 Oct 2009 23:39:47 -
> 0400:Hi,
> [snip]
> >The electrons must be recirculated in order to maintain a steady
> >current. If an electric field is the same as an EMF, then the 
> electric>field must form a closed loop, otherwise electrons would 
> pile up at the
> >'+'electrode where the electric field ends in your depiction. 
> 
> ...but they *are* "piling up"! (Actually they are already "piled 
> up", and the
> size of the pile is decreasing, IOW they are "piling down" ;).
> 
> In a capacitor there is a pile of electrons on one electrode, and a 
> paucity on
> the other. When the two are connected by a wire (of any shape), the 
> electronsfrom the pile flow through the wire to the other electrode 
> until both are equal
> at which point in time, the current stops (assuming the wire has no 
> inductance).In practice of course the wire always has some 
> inductance, so the current keeps
> going for a little while after zero charge has been reached due to 
> the collapse
> of the magnetic field around the wire, resulting in an opposite 
> charge on the
> capacitor. This gives rise to the decaying wave form seen after you 
> throw the
> switch that established the original connection.
> 
> In the case of a battery, the "pile" consists of the atoms of the 
> batteryelectrodes that either accept or donate electrons (depending 
> on the electrode).
> 
> >Of course
> >a closed electric field loop is not allowed in theory, so the 
> concept of
> >an electric field cannot
> >be used in a logically consistent manner to *fully* explain the 
> current.
> An electric field can and does explain the current, it's just *not* 
> a closed
> loop at the same voltage. The only place where a current flows at 
> the same
> voltage is in a ring of superconducting material where it flows 
> without loss and
> without an EMF at zero voltage drop. (one may also argue that an 
> atom itself is
> a superconductor allowing the electrons of the atom to "flow" 
> continuouslyaround the atom).
> 
> >Therefore an electric field IS NOT the same as an EMF.
> >
> Regards,
> 
> Robin van Spaandonk
> 
> http://rvanspaa.freehostia.com/Project.html
> 
> 

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[mixent]

In reply to  Harry Veeder's message of Thu, 08 Oct 2009 23:39:47 -0400:
Hi,
[snip]
>The electrons must be recirculated in order to maintain a steady
>current. If an electric field is the same as an EMF, then the electric
>field must form a closed loop, otherwise electrons would pile up at the
>'+'electrode where the electric field ends in your depiction. 

...but they *are* "piling up"! (Actually they are already "piled up", and the
size of the pile is decreasing, IOW they are "piling down" ;).

In a capacitor there is a pile of electrons on one electrode, and a paucity on
the other. When the two are connected by a wire (of any shape), the electrons
from the pile flow through the wire to the other electrode until both are equal
at which point in time, the current stops (assuming the wire has no inductance).
In practice of course the wire always has some inductance, so the current keeps
going for a little while after zero charge has been reached due to the collapse
of the magnetic field around the wire, resulting in an opposite charge on the
capacitor. This gives rise to the decaying wave form seen after you throw the
switch that established the original connection.

In the case of a battery, the "pile" consists of the atoms of the battery
electrodes that either accept or donate electrons (depending on the electrode).

>Of course
>a closed electric field loop is not allowed in theory, so the concept of
>an electric field cannot
>be used in a logically consistent manner to *fully* explain the current.

An electric field can and does explain the current, it's just *not* a closed
loop at the same voltage. The only place where a current flows at the same
voltage is in a ring of superconducting material where it flows without loss and
without an EMF at zero voltage drop. (one may also argue that an atom itself is
a superconductor allowing the electrons of the atom to "flow" continuously
around the atom).

>Therefore an electric field IS NOT the same as an EMF.
>
Regards,

Robin van Spaandonk

http://rvanspaa.freehostia.com/Project.html

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[Harry Veeder]

- Original Message -
From: mix...@bigpond.com
Date: Thursday, October 1, 2009 5:40 pm
Subject: Re: correction /Re: [Vo]:The Electric Field Outside a
Stationary Resistive Wire Carrying a Constant Current

> In reply to  Harry Veeder's message of Thu, 01 Oct 2009 02:20:00 -
> 0400:Hi,
> [snip]
> >> The "'positive' in between" is what makes the equations work 
> out. I 
> >> think you
> >> are having a problem because you expect the net EMF to integrate 
> to 
> >> zero (begin
> >> point = end point), which it would do if you take the "step" 
> into 
> >> account. Note
> >> that the EMF does not change monotonically around the complete 
> >> loop. It does
> >> along the wire (assuming a constant resistance/length ratio), 
> >> however there is
> >> at least one step when you hit the electrodes. (In the case of a 
> >> battery perhaps
> >> more accurately one step at each electrode).
> >> Regards,
> >> 
> >> Robin van Spaandonk
> >> 
> >> http://rvanspaa.freehostia.com/Project.html
> >> 
> >
> >Explaining the steady current in terms of EMFs does not lead to a
> >contradiction
> >so this is not where my problem lies. However, if the steady 
> current is
> >rigorously explained in terms of electric fields a contradiction 
> seems>to arise. 
> 
> How is EMF different from "electric field"? IOW why do not have a 
> problem with
> the former, but you do with the latter?

An ElectroMotive Force is a concrete arrangement of matter that comes
into being either by happenstance or by design and is capable of pushing
charges around. A 9 volt battery or a gas powered electrical generator
or a thunderstorm are examples of EMFs.  Even if we assume electric
fields are real -- in the sense of being more than just abstract
mathematical tools for making calculations and predictions -- they owe
their reality to a concrete arrangement of matter. In addition to this
ontological difference, there is also a logical difference which is born
out when you try to explain the current ONLY in terms of electric fields.


> >The steady current requires that the electric field lines
> >around the loop (i.e. from '-' to '-') form a closed path, 
> otherwise the
> >current would be  fleeting instead of steady. 
> >On the other hand this
> >contradicts the rule that electric fields cannot form a closed 
> loop when
> >the B field is not varying as is the case with a *steady* current.
> 
> ...but individual field lines don't form a closed loop. They end on 
> positive and
> negative charges in between. That's what the discontinuity is all 
> about that I
> mentioned in my previous post. It's where the voltage step happens.
>
> This is most clearly seen where the separator is a capacitor, and 
> no current
> flows through the dielectric of the capacitor. All you really have 
> is a "bent"
> wire connection with two ends. Current flows from one end to the 
> other.
> This is also true in a battery, but the break isn't as obvious as 
> it's at the
> atomic level, where electrons and ions separate. Actually there are 
> more like
> two breaks in a battery, one at each electrode, resulting in two 
> currents, an
> external electron current, and an internal ion current.
> 
> Regards,


The electrons must be recirculated in order to maintain a steady
current. If an electric field is the same as an EMF, then the electric
field must form a closed loop, otherwise electrons would pile up at the
'+'electrode where the electric field ends in your depiction. Of course
a closed electric field loop is not allowed in theory, so the concept of
an electric field cannot
be used in a logically consistent manner to *fully* explain the current.
Therefore an electric field IS NOT the same as an EMF.

Harry 

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[mixent]

In reply to  Harry Veeder's message of Thu, 01 Oct 2009 02:20:00 -0400:
Hi,
[snip]
>> The "'positive' in between" is what makes the equations work out. I 
>> think you
>> are having a problem because you expect the net EMF to integrate to 
>> zero (begin
>> point = end point), which it would do if you take the "step" into 
>> account. Note
>> that the EMF does not change monotonically around the complete 
>> loop. It does
>> along the wire (assuming a constant resistance/length ratio), 
>> however there is
>> at least one step when you hit the electrodes. (In the case of a 
>> battery perhaps
>> more accurately one step at each electrode).
>> Regards,
>> 
>> Robin van Spaandonk
>> 
>> http://rvanspaa.freehostia.com/Project.html
>> 
>
>Explaining the steady current in terms of EMFs does not lead to a
>contradiction
>so this is not where my problem lies. However, if the steady current is
>rigorously explained in terms of electric fields a contradiction seems
>to arise. 

How is EMF different from "electric field"? IOW why do not have a problem with
the former, but you do with the latter?

>The steady current requires that the electric field lines
>around the loop (i.e. from '-' to '-') form a closed path, otherwise the
>current would be  fleeting instead of steady. 
>On the other hand this
>contradicts the rule that electric fields cannot form a closed loop when
>the B field is not varying as is the case with a *steady* current.

...but individual field lines don't form a closed loop. They end on positive and
negative charges in between. That's what the discontinuity is all about that I
mentioned in my previous post. It's where the voltage step happens.

This is most clearly seen where the separator is a capacitor, and no current
flows through the dielectric of the capacitor. All you really have is a "bent"
wire connection with two ends. Current flows from one end to the other.

This is also true in a battery, but the break isn't as obvious as it's at the
atomic level, where electrons and ions separate. Actually there are more like
two breaks in a battery, one at each electrode, resulting in two currents, an
external electron current, and an internal ion current.

Regards,

Robin van Spaandonk

http://rvanspaa.freehostia.com/Project.html

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[Harry Veeder]

- Original Message -
From: mix...@bigpond.com
Date: Wednesday, September 30, 2009 6:09 pm
Subject: Re: correction /Re: [Vo]:The Electric Field Outside a
Stationary Resistive Wire Carrying a Constant Current

> In reply to  Harry Veeder's message of Wed, 30 Sep 2009 00:52:54 -
> 0400:Hi,
> [snip]
> >The complete circle/loop/circuit is this:
> >
> >'negative' to 'negative' (with a 'positive' in between).
> 
> The "'positive' in between" is what makes the equations work out. I 
> think you
> are having a problem because you expect the net EMF to integrate to 
> zero (begin
> point = end point), which it would do if you take the "step" into 
> account. Note
> that the EMF does not change monotonically around the complete 
> loop. It does
> along the wire (assuming a constant resistance/length ratio), 
> however there is
> at least one step when you hit the electrodes. (In the case of a 
> battery perhaps
> more accurately one step at each electrode).
> Regards,
> 
> Robin van Spaandonk
> 
> http://rvanspaa.freehostia.com/Project.html
> 

Explaining the steady current in terms of EMFs does not lead to a
contradiction
so this is not where my problem lies. However, if the steady current is
rigorously explained in terms of electric fields a contradiction seems
to arise. The steady current requires that the electric field lines
around the loop (i.e. from '-' to '-') form a closed path, otherwise the
current would be  fleeting instead of steady. On the other hand this
contradicts the rule that electric fields cannot form a closed loop when
the B field is not varying as is the case with a *steady* current.

Harry

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[mixent]

In reply to  Harry Veeder's message of Wed, 30 Sep 2009 00:52:54 -0400:
Hi,
[snip]
>The complete circle/loop/circuit is this:
>
>'negative' to 'negative' (with a 'positive' in between).

The "'positive' in between" is what makes the equations work out. I think you
are having a problem because you expect the net EMF to integrate to zero (begin
point = end point), which it would do if you take the "step" into account. Note
that the EMF does not change monotonically around the complete loop. It does
along the wire (assuming a constant resistance/length ratio), however there is
at least one step when you hit the electrodes. (In the case of a battery perhaps
more accurately one step at each electrode).
Regards,

Robin van Spaandonk

http://rvanspaa.freehostia.com/Project.html

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[Harry Veeder]

- Original Message -
From: mix...@bigpond.com
Date: Tuesday, September 29, 2009 10:51 pm
Subject: Re: correction /Re: [Vo]:The Electric Field Outside a
Stationary Resistive Wire Carrying a Constant Current

> In reply to  Harry Veeder's message of Tue, 29 Sep 2009 20:54:07 -
> 0400:Hi,
> [snip]
> >Yup, but that is not what bothers me. I have been unable to 
> >consistently apply the concept of an _electric field_ around 
> >a circuit with a steady current without it ending in a 
> >contradiction.
> >
> >harry
> That's because it's not really a complete circle. It's just a 
> "bent" path
> between two points, or more accurately two paths, one internal and 
> one external,
> but there are still two points, a positive connection point and a 
> negativeconnection point.
> 
> Regards,
> 
> Robin van Spaandonk
> 
> http://rvanspaa.freehostia.com/Project.html
> 
> 

The complete circle/loop/circuit is this:

'negative' to 'negative' (with a 'positive' in between).



Harry

Re: correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[mixent]

In reply to  Harry Veeder's message of Tue, 29 Sep 2009 20:54:07 -0400:
Hi,
[snip]
>Yup, but that is not what bothers me. I have been unable to 
>consistently apply the concept of an _electric field_ around 
>a circuit with a steady current without it ending in a 
>contradiction.
>
>harry
That's because it's not really a complete circle. It's just a "bent" path
between two points, or more accurately two paths, one internal and one external,
but there are still two points, a positive connection point and a negative
connection point.

Regards,

Robin van Spaandonk

http://rvanspaa.freehostia.com/Project.html

correction /Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire Carrying a Constant Current

[Harry Veeder]

- Original Message -
From: Harry Veeder 
Date: Tuesday, September 29, 2009 8:49 pm
Subject: Re: [Vo]:The Electric Field Outside a Stationary Resistive Wire
Carrying a Constant Current

> 
> - Original Message -
> From: mix...@bigpond.com
> Date: Tuesday, September 29, 2009 2:54 am
> Subject: Re: [Vo]:The Electric Field Outside a Stationary Resistive 
> WireCarrying a Constant Current


> > Because there's a pile of them in one place, and that pile gets 
> > smaller as the
> > capacitor/battery drains. Once it's empty, the current does 
> indeed 
> > stop.
> > Regards,
> > 
> 
> Yup, but that is not what bothers me. I have been unable to 
> consistentlyapply the concept of an electric around a circuit with 
> a steady current
> without it ending in a contradiction.
> 
> Harry

That should read:

Yup, but that is not what bothers me. I have been unable to 
consistently apply the concept of an _electric field_ around 
a circuit with a steady current without it ending in a 
contradiction.

harry