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chemoleo
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Superconductors and magnetism
Today I had a lengthy conversation with one of the NMR guys at work, and talked about superconductors and such things.
Basically, the question I had (and where we could find no answer) is - a superconducting coil (50 km long), essentially a coiled circular piece of
wire (which then becomes a permanent magnet), is charged up once, with (in this case) 160 A at 5 Volts. Now, first of all, how is it 'charged' up? I
mean- you guide a current through it, and at zero resistance you essentially short-circuit the power source unless you got a resistor of sorts
inbetween. Then you cap the connection, and the current keeps on running in the coil forever. How does this, precisely work?
From what I understand, electricity is the flow of electrons due to a potential difference between a electron-rich and electron-poor conductor. In the
case of the superconducting magnet, the coil - at any given moment, somewhere there will be a lack, and elsewhere an excess of electrons? Why then,
does it keep flowing- if the excess electrons could just 'diffuse' and fill the electron-poor regions, into both directions of the wire? How is the
potential difference, the electron-rich and poor regions within the circular wire maintained?
The other question relates to the magnetism induced by the superconductor.
This permanent magnet does apparently not need to be fed with more current, if objects, even ferro-magnetic ones, are moved within the magnetic field,
it does, according to my colleague, not weaken the magnetic field strength of the superconductor magnet.
So then - lets take this further - many have probably seen those hovering metal bodies that float above a superconductor, apparently they'd do that
forever. See the pic:
In the case of the big superconductor - I could basically keep a large weight hovering forever (like, say, a house, given a magnet big enough)? Or is
it forever? Does the field not become smaller with time, because of the constant 'friction' it is suffering by having to keep the object hovering?
In other words, where does the ever-lasting energy come from to keep a weight hovering forever? I mean, energy is expended by having to keep it
afloat. Where does it come from? The magnetic field of course. So wouldnt it decrease in strength?
I hope this is sort of clear. Both issues are quite paradox to me, probably due to a lack of understanding. I am sure someone can help on this
one...right?? 
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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garage chemist
chemical wizard
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Keeping an object afloat stationary does NOT require energy, similar as how the pull of gravity on a stationary object does not involve energetical
changes.
Think of the stable levitation with bismuth and neodymium magnets- the setup keeps the magnet afloat indefinately, without any change in magnetic
fields and even without cooling.
It is the same as balancing an object on a spring (I think everyone agrees that this does not require any energy once the object is balanced), only
here the spring is invisible. It's as simple as that.
And the inside of a superconductor is ENTIRELY free of electric fields. This is the definition of a superconductor.
The electrons keep circulating forever, since no force is acted upon them, due to the lack of electrical fields inside the superconductor.
They generate a stationary magnetic field exactly like a permanent magnet. Some energy is contained in the movement of electrons and in the field.
When a magnetic field is moved in the vicinity of a superconductor with no circulating electrons to start with, like in your picture of the floating
magnet, in such an order that the strength of magnetic field changes around the superconductor, the electrons start circulating because of induction
(eddy currents).
This circulation brings about the generaion of a secondary magnetic field that tries to counteract the first one (Lenz's law!) and repels the magnet
so that it floats. When the magnet is pulled upwards again, the direction of the currents reverses so that the magnet is attracted. So if you pull up
the magnet in the picture, the superconductor will be hovering in mid-air under the magnet (provided that the superconductor is a "hard"
superconductor, meaning that it can sustain a large enough current before it reaches the breakdown point and loses its superconductivity).
This principle also counteracts any movements the magnet is likely to do to fall off of the superconductr, like sidewards movements.
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Rosco Bodine
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Magnets are the most fascinating and enigmatic common objects
which have puzzled the minds of people for millennia .
They are humbling to the smartest person since their secrets ,
the actual mechanism of their behavior is
no more fully understood nor explained
than is gravity .
I am convinced that at a certain level , in a dimension
which humans do not fully understand , that a magnet
is indeed an " energy source " all by itself , which has
an effect at changing the property of space time in
its vicinity , relativistically acting in a similar way as
does a gravity source . To come near to understanding
magnets or gravity , one has to " put on the freak "
of relativistic conceptualizing and look through the
discerning eyes of Einstein .
It has been something suspected by me that the
opposition of gravity and magnetism which produces
levitation , is a kind of natural oscillator rather than
a static system , and it is inherently astable . If you
could look at the edge of the levitated magnet using
enough magnification and a high enough
frames per second sampling rate you could see in slow motion
that the levitated object is actually rising and falling
rapidly oscillating at the nuclear magnetic resonance
frequency or some harmonic thereof . It is also my
hypothesis that this is a " zero point " energy source
and a " free energy " system from which energy may
be secured by external means which introduces a
lower harmonic oscillation to the system , changing
the normal frequency of oscillation of the levitation
to a longer wavelength , so that the levitated object
rises and falls with sufficient vertical excursion that
the field disturbance generates electricity in external
coils by the magneto effect . So will the little
" magnetic sun " at the heart of this
" pickup coil universe " ever run down , its energy
being spent ? No . And where does the " energy "
come from ?
Don't ask me , you need to talk to somebody who
has really done some thinking about magnets 
[Edited on 24-2-2006 by Rosco Bodine]
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12AX7
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| Quote: | Originally posted by Rosco Bodine
Magnets are the most fascinating and enigmatic common objects
which have puzzled the minds of people for millennia .
They are humbling to the smartest person since their secrets ,
the actual mechanism of their behavior is
no more fully understood nor explained
than is gravity . |
Uh. No.
Honestly, must you speak on *any* subject involving moving electrons?
Nearly nothing is known about gravity. The last revolutionary work was basically done by Newton, Kepler and such.
Electromagnetism, on the other hand, involves electrons in a variety of moving and spinning (quantum spin that is) electrons. (I haven't personally
done any formal physics problems on creating magnetic fields, but that will come soon.)
| Quote: | I am convinced that at a certain level , in a dimension
which humans do not fully understand , that a magnet
is indeed an " energy source " all by itself |
Well, yeah, no shit, it stores a certain amount of current.
If you set up induction coils around a magnet and remove the magnetic field (such as by heating the magnet past its Curie temperature, mechanically
pulverizing it, or so on), the energy released by collapsing the field can be extracted.
Magnetic fields aren't very energetic, so you'll go through a *lot* of magnets trying to power a light bulb.
Conversely, a magnet is "charged" by applying a strong pulsed magnetic field in excess of the coercive force of the "hard" magnetic material it's
composed of.
| Quote: | | which has an effect at changing the property of space time in its vicinity |
Bullshit.
| Quote: | To come near to understanding
magnets or gravity , one has to " put on the freak "
of relativistic conceptualizing and look through the
discerning eyes of Einstein . |
Well, not really, Einstein was staunchly against quantum physics (even Plank and Schrodinger were, interestingly enough), but we see now that wave
theory is correct to a very reasonable degree.
| Quote: | the levitated object is actually rising and falling
rapidly oscillating at the nuclear magnetic resonance
frequency or some harmonic thereof . |
LMAO!
Oh...but... it gets better!!!
| Quote: | " zero point " energy source
and a " free energy " system from which energy may be secured |
Holy shit, you should go on tour as a stand-up comedian!
Tim
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12AX7
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Oh yeah, forgot I was going to post a useful reply to this!
| Quote: | Originally posted by chemoleo
Basically, the question I had (and where we could find no answer) is - a superconducting coil (50 km long), essentially a coiled circular piece of
wire (which then becomes a permanent magnet), is charged up once, with (in this case) 160 A at 5 Volts. Now, first of all, how is it 'charged' up? I
mean- you guide a current through it, and at zero resistance you essentially short-circuit the power source unless you got a resistor of sorts
inbetween. Then you cap the connection, and the current keeps on running in the coil forever. How does this, precisely work? |
Exactly like that.
Clearly, since it IS superconducting and has *zero* resistance, there must be current limiting present, *for DC*.
Timing can be used (since current through an inductance rises linearly with time), or a resistor can be used and the connection closed after a few RL
time constants (t = L/R, IIRC).
Remember, it's a coil of wire, so it has a magnetic field, proportional to loop current. The magnetic field stores energy roughly according to E =
1/2 * L * I^2 (the inductor's complement of E = 1/2 * C * V^2 for capacitor energy storage). Since it has an induced magnetic field, it also has
self-inductance, and thus electrical inductance. Thus, with an applied voltage, the equation dI / dt = V / L is true, and current rises linearly with
time for a constant voltage applied.
Although superconductors have zero resistance, it is thus possible to have voltage across the terminals of a superconducting unit. Current just goes
through the roof after a long time. 
Note also, from the equation, that if V is set to zero, dI/dt goes to zero. No change in current says nothing about the actual value of current, so
with voltage removed, it is possible to maintain a current in a perfect loop. Resistance of the wire tends to defeat this past a few seconds for very
bulky inductors (although there are some impressive examples using lots of wire and iron!), but superconductors can maintain it essentially
indefinetly. Effectively, such a superconducting magnet is a macroscopic version of a permanent magnet, which uses quantum effects (that, again, I
don't know enough about) to attain "frictionless" holding of the magnetic field.
| Quote: | | From what I understand, electricity is the flow of electrons due to a potential difference between a electron-rich and electron-poor conductor. In the
case of the superconducting magnet, the coil - at any given moment, somewhere there will be a lack, and elsewhere an excess of electrons? Why then,
does it keep flowing- if the excess electrons could just 'diffuse' and fill the electron-poor regions, into both directions of the wire? How is the
potential difference, the electron-rich and poor regions within the circular wire maintained? |
I'm not clear on the manner in which superconduction works. Something about cooper pairs, whatever those are. It certainly seems counterintuitive
that electrons can flow (thus having some kinetic energy in eV, electron-volts) despite zero voltage.
Come to think of it, perhaps the electrons are accelerated elsewhere (...power supply...), and the superconductor is, in effect, a piece of
super-teflon, allowing the electrons to move without friction?
AFAIK, this is similar to how permanent (room temperature  ) magnets work, only on
a smaller quantum level, which allows some materials certain energy states and orientations where orbits, spins and magnetic moments line up over
relatively long distances (magnetic domains). Being a quantum effect, there is a restriction of states, allowing it to remain magnetic. Although the
magnet is in a state of higher energy (heating past the Curie point and cooling will remove the field), it isn't enough energy on the quantum level to
raise it over the potential barrier to that lower energy state. Hence, in lieu of something to drive that change, energy is conserved and the energy
remains contained, as in the superconductor.
You can probably express superconducting magnets as large order magnets, although I'm certainly being dangerous going out on such a limb, especially
when so little is known of superconductors.
| Quote: | The other question relates to the magnetism induced by the superconductor.
This permanent magnet does not apparently need to be fed with more current, if objects, even ferro-magnetic ones, are moved within the magnetic field,
it does, according to my colleague, not weaken the magnetic field strength of the superconductor magnet. |
Correct. A superconducting loop is simply a magnetic dipole with some (large) coercive force. It's much easier, of course, to break the loop and
charge it up electrically.
| Quote: | So then - lets take this further - many have probably seen those hovering metal bodies that float above a superconductor, apparently they'd do that
forever. See the pic:
<snip--pic blows out the forum>
In the case of the big superconductor - I could basically keep a large weight hovering forever (like, say, a house, given a magnet big enough)? Or is
it forever? |
Sure. But you have to pay for the refrigeration, and especially over time (even in Alaska), it'd be a lot cheaper to install springs or stilts.
| Quote: | | I mean, energy is expended by having to keep it afloat. Where does it come from? The magnetic field of course. So wouldnt it decrease in strength?
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Veeeery careful there!! When *you* hold a weight at arm's length, it damn well does take power to hold it there. But when you put it on your
shoulders, the force is transferred through your skeleton, and it gets much easier to hold. Why? The answer is biological muscles wastefully expend
*power* to exert a *force*, whether or not the force is usefully being exerted over a distance (energy) or speed (power).
Once the house is placed on the magnet, energy is stored in the repelling magnetic fields, and changes can take place in that field, for example it
can bounce like a spring (that could make you nicely sea-sick!), but overall, the time integral (hah, I knew I could work calculus into this post!)
will equal the potenential energy of the system.
Tim
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bullstrode
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12AX7, superconductors don't work like that - most of your post is false. Just wiki it to find out how they work.
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12AX7
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| Quote: | Originally posted by bullstrode
12AX7, superconductors don't work like that - most of your post is false. Just wiki it to find out how they work. |
Well, the middle part certainly can be, but I wouldn't say "most" is. I'm quite confident to stand tall against the likes of you over the electrical
characteristics of an inductor or the properties of force vs. work vs. power, however.
Edit: In fact my analogy of super-teflon isn't far off. Wiki:
http://en.wikipedia.org/wiki/Superconductor
States the Cooper pairs flow as a sort of electron superfluid (comparable to supercooled helium), so in effect, yes, the quantum effects cause the
electrons to flow without friction (resistance).
Tim
[Edited on 2-26-2006 by 12AX7]
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Rosco Bodine
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| Quote: | Originally posted by 12AX7
| Quote: | Originally posted by Rosco Bodine
Magnets are the most fascinating and enigmatic common objects
which have puzzled the minds of people for millennia .
They are humbling to the smartest person since their secrets ,
the actual mechanism of their behavior is
no more fully understood nor explained
than is gravity . |
|
Uh . Yes , there hasn't been even close to an explanation
of either magnetism or gravity even though billions have been spent on researching both .
| Quote: |
Honestly, must you speak on *any* subject involving moving electrons? |
If I feel like I have something useful to add , I speak .
That's in constrast to some other folks for whom speaking
is like having a bowel movement .....it just happens
whenever the urge appears to be productive .
| Quote: |
Nearly nothing is known about gravity. The last revolutionary work was basically done by Newton, Kepler and such. |
Read more about Einstein . Then get back to me .
| Quote: |
Electromagnetism, on the other hand, involves electrons in a variety of moving and spinning (quantum spin that is) electrons. (I haven't personally
done any formal physics problems on creating magnetic fields, but that will come soon.) |
Electromagnetism is to natural magnetism something like current is to static electricity .......there is a difference
| Quote: | I am convinced that at a certain level , in a dimension
which humans do not fully understand , that a magnet
is indeed an " energy source " all by itself |
| Quote: | | Well, yeah, no shit, it stores a certain amount of current. |
I see , so a magnet " stores current "
Give this man the Nobel Prize because he just stated
for a fact something nobody else knows or maybe ever
will know .
| Quote: |
If you set up induction coils around a magnet and remove the magnetic field (such as by heating the magnet past its Curie temperature, mechanically
pulverizing it, or so on), the energy released by collapsing the field can be extracted. |
I think I can find better uses for magnets .
| Quote: |
Magnetic fields aren't very energetic, |
Really ? Then how are megawatts of power generated
from fairly compact alternators ?
| Quote: |
so you'll go through a *lot* of magnets trying to power a light bulb. |
Maybe using your ideas of power generation , but there are
better ways which leave the magnets intact .
| Quote: |
Conversely, a magnet is "charged" by applying a strong pulsed magnetic field in excess of the coercive force of the "hard" magnetic material it's
composed of. |
I always thought the term was magnetized and it is accomplished in different ways , the magnequench
process being one of the better ones .
| Quote: | | which has an effect at changing the property of space time in its vicinity |
Nothing but the facts . A " field " be it gravitational or magnetic is by definition " a property of space in the vicinity of an object " ,
so if you think a field is something else ,
please explain what else it is .
| Quote: | To come near to understanding
magnets or gravity , one has to " put on the freak "
of relativistic conceptualizing and look through the
discerning eyes of Einstein . |
| Quote: |
Well, not really, Einstein was staunchly against quantum physics (even Plank and Schrodinger were, interestingly enough), but we see now that wave
theory is correct to a very reasonable degree. |
And wave theory has exactly what to do with gravity
or magnetism ? You believe that the effects are due to
" something " emanating from the objects , an emission phenomena , rather than a spatial phenomena ?
Good luck with wave theory . The deeper you dig
the more you will believe that it is what we don't know
about space itself that is where the explanation resides .
All that " nothingness " in the distances between the
" somethings " we recognize is inextricably linked and
related to those " somethings " ....as much as is a
pool tables felt related to the billiard balls resting
upon it . Einstein knew this for a certainty not a theory .
And he was precisely correct on that score so far as
I know .
| Quote: | the levitated object is actually rising and falling
rapidly oscillating at the nuclear magnetic resonance
frequency or some harmonic thereof . |
Forces in equilibrium oscillate , just like a voltage regulator has ripple , there's just no getting around it .
| Quote: | Oh...but... it gets better!!!
| Quote: | " zero point " energy source
and a " free energy " system from which energy may be secured |
Holy shit, you should go on tour as a stand-up comedian!
Tim |
I try to keep a sense of humor , even when it's a tough crowd , and like Rodney Dangerfield .....I get no respect
[Edited on 27-2-2006 by Rosco Bodine]
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chemoleo
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Well thanks for the replies.
I had a look around in Wiki and other sources, too.
| Quote: | | From what I understand, electricity is the flow of electrons due to a potential difference between a electron-rich and electron-poor conductor. In the
case of the superconducting magnet, the coil - at any given moment, somewhere there will be a lack, and elsewhere an excess of electrons? Why then,
does it keep flowing- if the excess electrons could just 'diffuse' and fill the electron-poor regions, into both directions of the wire? How is the
potential difference, the electron-rich and poor regions within the circular wire maintained? |
I think my mistake was in thinking that a charge difference is required to get electrons to flow uniformly. Not so, it seems. From Wiki:
| Quote: | In a normal conductor, an electrical current may be visualized as a fluid of electrons moving across a heavy ionic lattice. The electrons are
constantly colliding with the ions in the lattice, and during each collision some of the energy carried by the current is absorbed by the lattice and
converted into heat (which is essentially the vibrational kinetic energy of the lattice ions.) As a result, the energy carried by the current is
constantly being dissipated. This is the phenomenon of electrical resistance.
The situation is different in a superconductor. In a conventional superconductor, the electronic fluid cannot be resolved into individual electrons,
instead consisting of bound pairs of electrons known as Cooper pairs. This pairing is caused by an attractive force between electrons from the
exchange of phonons. Due to quantum mechanics, the energy spectrum of this Cooper pair fluid possesses an energy gap, meaning there is a minimum
amount of energy ΔE that must be supplied in order to excite the fluid. Therefore, if ΔE is larger than the thermal energy of the lattice
(given by kT, where k is Boltzmann's constant and T is the temperature), the fluid will not be scattered by the lattice. The Cooper pair fluid
is thus a superfluid, meaning it can flow without energy dissipation. |
Details aside - the issue of course is that electrons can flow without resistance. Thus, if they are pushed, in a certain manner, by a magnetic field,
currents are induced (that produce a magnetic field exactly counteracting that of the external field, producing this floatation-effect (The
absorption of the magnetic field is seemingly extremely efficient, it penetrates the superconductor no more than 100 nm (Meissner effect) - so
superconductors are perfect magnetic field cancellers - except they create one by themselves). These currents can keep on flowing, forever, because of
zero resisitvity. Why is there no voltage difference? Because the electrons flow, as a mass of them, just in one direction, as would i.e. superfluid
helium in a circular tube, where there was no resistance whatsoever. Thus, there is zero voltage, and a high current (whose amperage depends on the
strength of the externally applied field?). Does that make sense, and did I understand this correctly?
However- say, I pass by a superconductor permanent magnet with a large coil. A current is induced in this coil. This in turn makes a magnet field,
which in turn induces a current in the superconducting magnet - a current that will run counter to the one present, and thus reduce the force of the
superconductor magnetic field. Right? So this would be a mechanism to screw up the field strenght of the superconductor?
Ah, this is all so weird. I know for instance, that if the superconductor coil in a magnet is allowed to rise in temperature, past its critical point,
it heats up, and it starts boiling helium gas. Thus, there IS stored energy in a superconductor. Now, if I take that superconductor, and separate the
wire, the electron fluid flow essentially stops. What happens to the stored energy?
As to floatation of the magnet - say I put an uncharged supermagnet into vacuum, into space, and surround it by a vast number of magnets, similiar to
the picture shown above. Then, I charge up the central magnet. All of the smaller magnets are accelerated, and they move away. That takes
energy, where does it come from? Or rather, shouldnt the field of the central magnet be weakened? Arrrgh!
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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12AX7
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Rosco: I don't see a post, it looks like you just quoted my entire post??
| Quote: | Originally posted by chemoleo
These currents can keep on flowing, forever, because of zero resisitvity. Why is there no voltage difference? Because the electrons flow, as a mass of
them, just in one direction, as would i.e. superfluid helium in a circular tube, where there was no resistance whatsoever. Thus, there is zero
voltage, and a high current (whose amperage depends on the strength of the externally applied field?). Does that make sense, and did I understand this
correctly? |
Ya- and the electrons then have some velocity too, and thus kinetic energy e*V, but then because it's a loop, the voltage would translate to magnetic
field (measured in webers = volt-seconds). Ah, that makes neat sense of things
| Quote: | | However- say, I pass by a superconductor permanent magnet with a large coil. A current is induced in this coil. This in turn makes a magnet field,
which in turn induces a current in the superconducting magnet - a current that will run counter to the one present, and thus reduce the force of the
superconductor magnetic field. Right? So this would be a mechanism to screw up the field strenght of the superconductor? |
When applied field equals the loop's field strength, the electrons would stop moving. More and they would go in the opposite direction. An opposite
field would cause them to move faster. But below the critical field strength, I don't think there's a way to change the current in, or field produced
by, the loop. Conservation of energy, and probably that magnetic fields can't induce motion, only radial acceleration. (Particle accelerators use
magnetic fields for *containing* charged particles; electric fields must be used to actually move the particle.)
| Quote: | | Ah, this is all so weird. I know for instance, that if the superconductor coil in a magnet is allowed to rise in temperature, past its critical point,
it heats up, and it starts boiling helium gas. Thus, there IS stored energy in a superconductor. Now, if I take that superconductor, and separate the
wire, the electron fluid flow essentially stops. What happens to the stored energy? |
You mean open the electrical circuit?
The electrons would tend to continue moving (law of induction), so the terminal voltage would rise as fast as the current allows (the 100A or whatever
is *still* flowing in the loop!). Eventually, the voltage (excess or absence of electrons: essentially, they bunch up in one end!) becomes so great
that it jumps the gap and you get a spark.
The total amount of energy, then, is manifested as a plasma discharge.
If instead you open the circuit to a capacitor, the terminal voltage will rise according to the current charging it, until the pressure of the
electrons becomes greater than the remaining magnetic field pushing them to the one end. If you disconnect the inductor at zero current, you then
have the energy stored in a capacitor, rather than the inductance.
If you open the circuit by first connecting a resistor across the terminals and then disconnecting the superconductor, the contained energy discharges
according to the LR time constant (an exponential decay).
Electromagnetic radiation also plays a small part in this, although you can easily ignore it in most cases. A superconducting magnet may be a more
special case, since it has an unusually strong field.
| Quote: | | As to floatation of the magnet - say I put an uncharged supermagnet into vacuum, into space, and surround it by a vast number of magnets, similiar to
the picture shown above. Then, I charge up the central magnet. All of the smaller magnets are accelerated, and they move away. That takes
energy, where does it come from? Or rather, shouldnt the field of the central magnet be weakened? Arrrgh! |
Actually I would expect the magnets (which are dipoles after all) to rotate towards the larger magnet and be attracted. Repelling tends to be a state
of higher energy than attraction, as you well know from playing with magnets.
Speaking of which, in the earlier paragraph asking about an applied field, don't forget that it will "fight" the superconducting magnet and cause a
torque between the two sources as the dipoles would prefer to be aligned.
Tim
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Rosco Bodine
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| Quote: | Originally posted by 12AX7
Rosco: I don't see a post, it looks like you just quoted my entire post?? |
Take another look , see if it makes more sense now .
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IrC
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Tim, you rely too much on established electromagnetic theory without going deeper. Maxwell came up with his displacement current from the work of
Ampere. The problem is that when Maxwell did his work he, as all others did at this time, could only imagine an "aether". What Maxwells displacement
currents were in his mind was the "displacement of aether", and further work by Heavyside simplified equations removing quaternions but again relying
on the original errors only compounded the situation. This is one of the reasons why science today still cannot truly answer the superconducting
question. I see in your posts that you are so founded on the formal teachings that you are going to end up with all the other scientists who fail to
answer the fundamental questions in this field. I think you should look more into other posts here and keep an open mind instead of relying so much
upon the book learning you have. If the books had it all correct then we would have no mysteries, whether superconductivity or gravity was the
question.
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Rosco Bodine
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When it comes to the matter of practical engineering
as well as science Maxwell stands tall enough that
his work is essential to the technology we have today .
You can double check the output of computer generated
structural analyses for accuracy against the results
you get from graph paper and a carefully drawn
Maxwell Diagram , and * if * the results differ......
then you need to find out what is wrong with the computer or the computer model . On the day you
even think you are smart about trigonometry and
physics , try to explain exactly how it is that a
" simple " Maxwell diagram works , and be humbled
For a practical example of a real world application ,
there is a full cantilever freespan ironwork railroad trestle
across a body of water " the Firth of Forth " in Scotland ,
not a " suspension " type bridge as is the usual for spanning an opening of 1700 feet ,
but an end supported full cantilevered beam ,
across which trains can travel
Built 1890 ........over a hundred years ago .
" Beam " me up " Scotty "..... the deflection in the middle
when the ore train goes across is just killing me
http://en.structurae.de/structures/data/photos.cfm?ID=s00000...
Take a look .
http://www.brianseamens.pwp.blueyonder.co.uk/FORTH/index.htm
[Edited on 27-2-2006 by Rosco Bodine]
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12AX7
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| Quote: | Originally posted by IrC
Tim, you rely too much on established electromagnetic theory without going deeper. Maxwell came up with his displacement current from the work of
Ampere. The problem is that when Maxwell did his work he, as all others did at this time, could only imagine an "aether". |
I try to keep an open mind. If you happen to have data that contradict's Maxwell's equations, I would be quite interested in seeing it.
I'm just presenting the facts (can someone please restrict Rosco's access or something? his brain drain is killing me) as I know them, if you have
better information (which I notice you have not presented), please post.
Tim
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Rosco Bodine
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@12AX7
Sheeesh ......to cut some people to the quick ,
a person could be hacking away at them all day
and still never find it
What is the brain drain of which you speak anyway ?
I sure didn't mean to lower the level of discussion
in any topics where you post .
[Edited on 27-2-2006 by Rosco Bodine]
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IrC
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http://www.theradicalremnant.com/max_booklet.pdf
Here is some interesting reading about it, if I could remember the URL I will post another site with very in depth work on it. It seems to get back to
Maxwell you have to do so HIS WAY. By this I mean you must undo the work of heavyside (I never remember how to spell that name), and put back the
quaternion math, only then will you have the work of maxwell. Problem is it seems like diamonds are easier to find than his original books, and they
are so big I am not going to scan them. It took me 40 years to even find them. No doubt his work is fundamental in many areas of science and correct
but certain specific problems keep us from doing what we all want so much.
That is, antigravity, zero point power, real room temperature superconductivity which wont blow out when hit with a multi tesla magnetic field, and in
general all kinds of neat cool stuff we seem to be mind blocked over for the last hundred years or so. I am not a math guru and I cannot find his
original work using quaternions, so it would be extremely hard to recreate exactly his work, but learning the math and working with his equations will
point out problems such as inventing the displacement, and the poynting vector error which remains unsolved. This is related to the power flow in a
circuit, where doing the math shows clearly that electrons move down a wire slower than molasses dripping while power magically appears to come into
the circuit in a plane perpendicular to the actual physical circuit (by magically I mean from space itself outside the actual circuit!). Interesting
stuff, I wish I was smart enough to solve it all.
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Twospoons
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| Quote: |
As to floatation of the magnet - say I put an uncharged supermagnet into vacuum, into space, and surround it by a vast number of magnets, similiar to
the picture shown above. Then, I charge up the central magnet. All of the smaller magnets are accelerated, and they move away. That takes energy,
where does it come from? Or rather, shouldnt the field of the central magnet be weakened? Arrrgh!
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The energy comes from the stored field energy in the superconductor, which will decrease as the other magnets accelerate away. As some smart cookie
will undoubtedly point out "If theres no resistance, therefore no voltage, where does the energy in the ring come from?" - it comes from the effort
expended in closing the loop!
Helicopter: "helico" -> spiral, "pter" -> with wings
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12AX7
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| Quote: | Originally posted by IrC
http://www.theradicalremnant.com/max_booklet.pdf
Here is some interesting reading about it, if I could remember the URL I will post another site with very in depth work on it. It seems to get back to
Maxwell you have to do so HIS WAY. By this I mean you must undo the work of heaviside, and put back the quaternion math, only then will you have the
work of maxwell. Problem is it seems like diamonds are easier to find than his original books, and they are so big I am not going to scan them. It
took me 40 years to even find them. No doubt his work is fundamental in many areas of science and correct but certain specific problems keep us from
doing what we all want so much. |
Meh. I'm not too convinced. He explains the "accepted" equations reasonably, but in positing his theory, he presents no formulae or quantification,
only hand waving.
| Quote: | | That is, antigravity, zero point power, real room temperature superconductivity which wont blow out when hit with a multi tesla magnetic field, and in
general all kinds of neat cool stuff we seem to be mind blocked over for the last hundred years or so. |
That sounds distinctly like a conspiracy theory...(tell me, was this also kept down by "the man"?)
| Quote: | | This is related to the power flow in a circuit, where doing the math shows clearly that electrons move down a wire slower than molasses dripping while
power magically appears to come into the circuit in a plane perpendicular to the actual physical circuit (by magically I mean from space itself
outside the actual circuit!). Interesting stuff, I wish I was smart enough to solve it all. |
Well, the wavefront of incoming energy is naturally more or less perpendicular to the surface I guess, but considering it is travelling
parallel to the surface, that's not a very useful notion.
As for electron flow, it does indeed drip slower than molasses, but there's a metric shitload of electrons in a piece of copper, so you can quite
easily get a lot of coulombs moving through a cross-section in a short time, nonetheless. In addition, the repulsive forces propagate the signal near
the speed of light, making wires very practical.
Tim
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IrC
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"That sounds distinctly like a conspiracy theory...(tell me, was this also kept down by "the man"?)"
Only in the mind of the very paranoid. I never stated anyone was keeping anything hidden, merely stated the obvious and that is NO TIM, WE DO NOT KNOW
HOW TO DO THESE THINGS. If we did, they would likely be on sale at Walmart already. Nothing like a good hoverboard. The point I was making is that if
the science you swear by was so good we would have already invented the things I mentioned. A conspiracy? Be real, we don't even know the most
fundamental things (meaning the most simple). Therefore to swear by such limited knowledge is arrogance run amuck. As to the read I posted it was to
give you an idea, I did mention I don't remember the URL of the people who go into depth over this, and since it would take hours to find it is not
worth me looking if you are going to keep missing the point and nitpicking. It is a fact about Maxwells displacement current, but I expect since you
have not actually read his work fully but rather rely on the teachings of it by others, that you do not or can not see my point.
"As for electron flow, it does indeed drip slower than molasses, but there's a metric shitload of electrons in a piece of copper, so you can quite
easily get a lot of coulombs moving through a cross-section in a short time, nonetheless. In addition, the repulsive forces propagate the signal near
the speed of light, making wires very practical."
Again you completely missed the point, and cover this by going off on a tangent talking about how good copper conducts as if I was saying it did not,
missing the poynting vector and power flow paradox completely. I can only assume your study is incomplete or you already would have been familiar with
all of this anyway. However, I don't have time to do a dissertation for you, hopefully others out here who wish to see the point and do the searching
and work will find some new interesting knowledge. Obviously you already are convinced you have all the knowledge you need for life so no more can I
say to you.
[Edited on 28-2-2006 by IrC]
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IrC
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12AX7, you made me work my ass off. I had lost my bookmark to this site and I wanted to give this PDF file to show some paradoxes which should make
you take another look at the science taught in schools. I could not find the file as I have over 4,000 CD's of info and could not remember the site or
any keywords which would make is easily show up in a billion hits about Maxwell. I looked for weeks and finally found it, the PDF here has links in it
if anyone wishes to visit the site and read more.
Just for Tim:
http://www.theradicalremnant.com/stuff/apoce.pdf
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cbfull
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Some physicists consider the field produced by a magnet to be a type of photon. The more familiar type of photon (light) is created when an electron
moves very suddenly in a transverse fashion. The only electrons that can interact with the light wave are the ones that can also change position in
exactly the same amount (not 100% sure about that last part).
With magnetic fields, the electrons are moving in a circle, and can only interact with other electrons already moving in a circle, or can be
influenced to move in an unobstructed circular path.
The simpliest way to understand the levitating magnet is to think of it as seeing it's own reflection in the superconductor, just like light waves
reflecting off of a mirror.
Hope this helps.
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franklyn
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I'll try to explain
Electrons as we all know are always in motion within their host atom.
They remain there unchanged except when an external input of energy
disturbs its gyrations. It is a useful fiction to think of this as a
frictionless flywheel. In a conductor , valence electrons are free
to move among adjacent atoms, and do so all the time from ambient
heat, similar to Brownian motion. An applied electric field provides
a bias to this chaos introducing a vector which causes the drift
called the current.
At temperatures above superconducting effects, electrons drift as
individuals. The applied energy from the electric field causing the
drift manifests itself as heat , as electrons gain energy and move
to an adjacent atom or fall back to the same one , shedding energy.
At a low enough temperature there are no external thermal effects
and the acting electric field is the only influence affecting electron
displacement. A new effect now takes place and these free wandering
individual electrons join to form a pair and move together as if they
are one particle. The pairing explains why a superconducting medium
is diamagnetic, since there are no available unpaired electrons to
convey a magnetic field. Any external magnetic field is repelled by
a counter opposed field induced in the superconductor by the external
field and exactly counteracts any lateral motion. Because unlike the
fixed electrons of a permanent magnet , these electrons are able to
drift and match the external field without regard to imposed lattice
geometry. This is the observed Miesner effect. The analogy of the
frictionless flywheel is now most appropriate , the drift acquired is
no longer shed and no additional energy input is required to maintain
this flow.
In a permanent magnet unpaired electrons gyrate fixed to their host
atom. The tendency over time is for thermal effects to cause
adjacent atoms to form a couple with the fields of their individual
unpaired electron , thus lowering its energy state , you could call
this it's enthalpy. These electrons are not however paired and remain
attached within their individual host atom. When a bias magnetizing
field is applied to the magnet material , all of these domains become
oriented so that their fields merge macroscopically instead of being
contained within just a few atoms. Again , with the application of
heat these electrons are once again able to vary their set orientation
and the larger magnetic field is diminished.
Its important to distinguish the origin of magnetism from a source.
Permanent magnetism rises from the polarized electronic structure
of an atomic lattice and is a scalar field because the electrons
involved have no drift ( if they did drift macroscopic magnetism
would cease ). Conductivity within a metal lattice is brought about
from an applied external field either electric or magnetic , and is a
vector field because these electrons drift ( if they did not there
would be no magnetic field present ).
Can you have both types present in the same system ? Yes, this
gives rise to all sorts of known magnetic effects and new ones
being discovered all the time to numerous for me to attempt to
list. A very useful reference to all this is ->
Handbook of Magnetic Phenomena by Harry E. Burke
Van Nostrand Reinhold 1986 ISBN 0-442-21184-8
.
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Nerro
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Hear hear! finally info from someone who knows what he's talking about!
Can you perhaps explain why FeO and Fe2O3 are diamagnetic while FeO.Fe2O3 ís paramagnetic? It seems to make little sense to me. Is it caused by the
fact that the Fe atoms in FeO have 1 "free" valence electron that is forced to stay put within the crystal lattice? That would seem to fit in your
explanation.
#261501 +(11351)- [X]
the \"bishop\" came to our church today
he was a fucken impostor
never once moved diagonally
courtesy of bash
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franklyn
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| Quote: | Originally posted by Nerro
Can you perhaps explain why FeO and Fe2O3 are diamagnetic while FeO.Fe2O3 ís paramagnetic? |
I'm by no means expert in the field, it is highly specialized and the
subject of an endless presentation of papers in physics journals.
There are a few variations on the theme of permanent magnetism
all of it related to the physical structure and atomic organization of
the materials involved. Most any textbook on the subject will explain
at length the differences. Basically there is ferro magnetism, para
magnetism, ferrimagnetism, anti-ferri magnetism, diamagnetism, and
a host of effects manifesting aspects of these alone or in combination.
.
[Edited on 24-6-2006 by franklyn]
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Nerro
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Is it likely that these are all manifestations of a single effect yet to be discovered?
#261501 +(11351)- [X]
the \"bishop\" came to our church today
he was a fucken impostor
never once moved diagonally
courtesy of bash
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