author=picowatt link=topic=4661.msg112099#msg112099 date=1715487478
I do not believe a gradient is required for a Hall effect probe to function. However, no change in field strength or polarity is detected as the probe is moved along the side of the magnet with its detection axis parallel to the magnetic axis. If there was an extra or opposite pole at each end with a null in the middle, surely this would create even greater gradients that can be detected. As previously stated, even moving the probe through an area that appears to be a null or bloch wall when observed with viewing film, no such null or any polarity reversal is detected with a Hall probe.
Why would you detect a neutral point using a hall probe along the magnets length, when the field gradient remains the same value along the length of the magnet?
So doing my best to explain, we need to view the field as a cloud of !charged! particles, where one end of the magnet has a negative net charge, and the other a positive net charge. (i will get to the type of charge in one of your later responses). So looking at my first scribble below, where it is only 2 dimensional, (but should be viewed a 3 dimensional), we can see that when the hall probe is slid from one end to the other, the same field gradient value exists along the length of the magnet that the hall probe would encounter, resulting in your hall probe showing the same result all along the magnets length.
Now, the second diagram shows the same thing, but this time using a voltage dropped across a resistive carbon rod.
With the two DMM probes fixed, so as the same distance between the probes is maintained, such as the junction in the hall probe is, regardless of the fact that we both know that one end of the carbon rod has a net positive charge, and the other a net negative charge, the DMM will read the same voltage at any two fixed points along that resistive rod.
Now, if we use a ferromagnetic rod, like that used for the core of a coil, at the center of the magnet, the rod would see an even negative and positive value, which means a net value of 0.
If this coil core is move to the left, it would see a net positive value, and if moved to the right, it would see a net negative value, which is why we would get opposite sines from right to left of center, and a 0 value emf at the center position.
As well, I suspect a homopolar generator/motor would also function with just one pole of a magnet facing the homopolar disc and the other pole directed away using a long magnetic armature, but that is another topic for discussion.
Yes it will work with just one magnet on one side of the disk, but the field gradient is still their through the disk.
By placing another magnet on the opposite side of the disk, with the two opposite fields facing the disk, far more current, and a higher voltage is produced, as the disk now sees a far greater field gradient.
For now let's stick to whether the field around a PM is as you propose or as it is conventionally envisioned.
I would ask, who decided the field convention? and what instruments were used back then to conclude such a convention?
What is the magnetic force?. What is it made of?
The conventional magnetic field theory does not answer this fundamental question.
The equal but opposite regarding a PM are its vectors. With regard to a PM, I would not use the word "charge".
The vectors and field lines are man made constructs, in the hope of describing what a magnetic field is.
In reality, the fields should be viewed like clouds of charge, where the charge density is greatest at each pole.
Are you equating electrical charges to the poles of a PM? I would not.
I am guessing you have not read the whole thread, where i explain as to what type of charges i believe they are, which is not the conventional electric charge as we know it.
I believe the PM is separating some other kind of charge that exists within an energy field that exists in all space.
Perhaps this dark energy they speak of, or vacuum energy, or the Aether.
The arrows do not indicate "flow", They are merely vectors (although I have seen some seemingly use the vectors to indicate "flow", I would not). The bigger clue is which way are electrons deflected at opposing poles...
I would agree that there is no flow of anything, but only a separation of some kind of charge.
If nothing is flowing or moving, what is it that is deflecting the electrons?
In order for an electron to be deflected, energy is required. Where or what is this energy if nothing is flowing or moving?
We know that photons, although massless, can move an electron, as they (the photon) have energy due to motion.
So what moves or deflects electrons in a magnetic field?
I myself would be inclined to not use words like "flow" or "flowing" when describing a PM.
Neither would i, but many people do.
So once again, where does the magnetic field get it's energy from to deflect an electron, which has mass?
The fields at the poles are indeed opposite but only in that the vectors point in opposite directions at each end.
If there is no flow or motion, what are these !vectors!?
What do the arrows (vectors) show?, if nothing is moving.
At the north, we have the arrows pointing out of the magnet body, and the south end, we have the arrows pointing into the magnet body.
If nothing is exiting or entering the magnet (no flow), then what exactly do these vector arrows show?
Again, they are merely vectors, they do not indicate "flow" or motion.
So if the field is static, then how can there be a direction associated with the vectors?
How is it that although the same static field (nothing flowing) exists at each end of a magnet, we can say-well one end the field is pointing in, and the other it is pointing out.
As in my first post, the Hall probe demonstrates which way electrons are deflected,
Where is the energy coming from to deflect the electrons?
if one could see through the face of the magnet to the opposing face, we would see that the electrons are deflected in the same direction at each pole,
Which would mean that one end would have a negative charge, and the other a positive charge.
However, I disagree with your idea of two separate and opposite poles at opposing ends of a magnet with some sort of null in the middle.
Everything i have shown, shows a neutral point at the center of the poles of a magnet, along with many others here.
My 2 field theory explains exactly why you see what you see with your hall sensor.
It explains as to why opposite poles attract, and like poles repel.
It explains why a piece of ferromagnetic material will not stick to the center portion of the magnet between the poles.
And it explains why passing the center point of a magnet pass the core of a coil will not induce an emf across that coil.
You claim that your hall sensor shows the same field along the length of the magnet, and so it should produce an emf across a coil when any portion of that magnet is passed across the core of the coil-but it does not.
I also believe the jury is still out with regard to whether the field rotates with the magnet. Personally, I believe it does
If that were the case, we could spin either the disk or the magnet in a homopolar generator, to generate a current flow through the disk.
But this is not the case. We can spin the magnet as fast as we like, but no emf would appear across the disk, and no current will flow through the disk, as no charge separation takes place.
This can only mean that the magnetic fields are pinned to the surrounding space of the magnet body, and is not part of the magnet body it self.
In order to generate current flow through the disk, there must be relative motion between the magnets fields, and the copper disk.
So, if the magnetic fields actually moved with the magnet body, then would could just spin the magnet to get that relative motion between the magnetic fields, and the disk.
This would mean we could pull electrical energy from the disk, without having to use brushes and the likes to collect that electrical energy.
We could solder one wire to the outer rim of the disk, and the other to the center of the disk, and just spin the magnet=a pure DC brushless generator and motor would be had.
But as i am sure you are well aware, this does not work.
While I will agree that scientists don't know everything, they do know quite a lot with regard to the geometry of magnetic fields. Look what they are able to accomplish with computer simulations and reductions to practice regarding Tokamaks and Stellerators, MRI machines or highly efficient PM motors. A new theory regarding what a magnetic field actually "is" will embrace and enhance our current understanding and explain why the fields are shaped and behave as they do. It won't prove all the scientists' observations wrong, it will explain them in a new light.
The 2 field theory changes nothing about the workings of any magnetic device.
But what it does do, is explain what the magnetic field is, what the magnetic force is, and why like poles repel, and unlike poles attract.
I mean, you really just have to stand back and look at all the effects we see with magnetic fields, where the two field theory explains them all.
Think about what happens when say a piece of neodymium is magnetized.
We zap it with a strong electromagnetic field- all the electrons (well most) are deflected in the same direction, and then all of a sudden, we have this invisible !force field! just appear out of no where.
I say force field, as this invisible field can apply a force to another such invisible field.
Where did this force field come from if nothing flows out of, or into the PM?
I stand by my claim.
That field already existed around that PM body before it was magnetized, in a neutral state, as it does in all space. It never just spewed out of the magnet once it was magnetized.
Once all those little generators (electrons) were all working together( material magnetized), then caused the separation of charges that already existed in a neutral field around the PM body.
There is nothing that the two field theory does not work for, and it explains what the magnetic field is, and how and why it can exert this invisible force.
Brad
Never let your schooling get in the way of your education.
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Topic: On the notion of a magnetic motor (Read 22846 times)
