Magnet Myths and Misconceptions

[Newton II]

A continuous flow of unchanging DC current will produce a continuous unchanging magnetic field.  Easily confirmed by experimental observation.

I know that a uniform DC produces unchanging magnetic field at the centre. 

Whether this unchanging flux remains static or rotates around a vertical axis following the path of moving electrons? When a moving electron produces magnetic field, the magnetic field should also move along with it, is it not?

Will the  magnetic field produced by a permanent magnet remains static or will it rotate around a vertical axis following the path of electrons producing that magnetic field?

If you don't understand my question- leave it - no problem.

The existance of magnetic field, transformation of electric field to magnetic field and other strange properties of magnetic field are beyond the scope of ordinary cracknuts. Better forget about all those things and enjoy playing with 'magnetic black holes'.


https://www.physicsforums.com/threads/why-does-moving-electron-produce-magnetic-field.184619/

http://en.wikipedia.org/wiki/Quantum_vortex

[Marsing]

someone said in TA thread that magnetic field is move at ~60x speed of light, magnetic field is not static but i dont know he said that for PM or electromagnet (coil) or both. i can not recall his name. 

[poynt99]

I have said 'force or vibration of a moving magnetic field'. 


If you pass an AC through a coil and take a iron piece near the coil, iron piece vibrates indicating that the magnetic field produced by coil is in some sort motion or oscillation.

But if you pass a DC through the coil and bring a iron piece near it, you won't feel any vibration of the iron piece and it simply gets attracted to the coil indicating that magnetic field is stagnant.

There really is no difference between these two scenarios.

My question is why moving electrons in a DC produce static magnetic field in the coil? 

This is the pertinent question.

But I don't think the question is "why" as much as it is "how". I believe the magnetic field is produced because the electron field around the individual atoms become aligned with each other.

But how does applying a DC voltage/voltage cause this alignment? There does not seem to be a maximum alignment like there is with aligning domains in a core material.

[mondrasek]

But I don't think the question is "why" as much as it is "how". I believe the magnetic field is produced because the electron field around the individual atoms become aligned with each other.

But how does applying a DC voltage/voltage cause this alignment? There does not seem to be a maximum alignment like there is with aligning domains in a core material.

I had not considered this before.  The relationship between current "flow" and the corresponding magnetic field "strength" increases as 1:1 (heating losses aside) as far as testing has shown?  There is no apparent, or theoretical limit?

[MileHigh]

Newton II:

I could not fine the right clip to link to yesterday, but I found it today:

"Calculating the Magnetic Field due to a Moving Point Charge"

https://www.youtube.com/watch?v=waTF7kjmmt8&list=UU6x7DywfEqLg-3Cg_JnyTlg&index=47

So for a moving point charge you can say that it is any value of charge, even the charge associated with a single electron.  If you watch the clip you will see that there is a magnetic field that envelopes the single moving electron and it moves along with the electron.

Magnetic fields are vectors with magnitude and direction.  If you have multiple magnetic field vectors at a single point in 3D space due to multiple moving electrons in a wire, then they all add together.

So, you do have a moving magnetic field for each moving electron.  So each distinct point in 3D space around the wire is affected by trillions and trillions of magnetic field vectors due to trillions and trillions of moving individual electrons.  The net result of all of these trillions and trillions of magnetic field vector additions when you have DC current is that you have a single unchanging magnetic field vector at a given point in 3D space.

It's as simple (or complicated) as that.

One of the myths is that when you hold two magnets with opposing poles next to each other and you feel the repulsion between the poles that you have "stressed space" in the region between the two opposite poles.  That's just a myth.  A person feels the repulsion and says, "that must be special stressed space."  The magnetic field vectors from each magnet are simply passing through the same 3D space and crossing paths without even being "aware" that the other magnet is there.  The magnetic field vectors are just "blindly" adding together to create a new net magnetic field with a new magnitude and direction at every point in 3D space.

Another myth is that people believe that something must be "circulating around" because they look at diagrams with magnetic field lines of force represented as circles with directional arrows.  It's just a myth self-created from looking at diagrams on paper.

You can just as easily feel forces between two charged objects due to an electric field between the two objects but that is a much rarer occurrence for experimenters so they don't even think about it.

You can "stress" space with electric fields and magnetic fields.  What actually is an electric field?  What actually is a magnetic field?   I don't know but it almost like going up to taste tester for a five star restaurant and asking him to describe the taste of water.