Home  |  About  | Last |  Submit  |  Contact
AllQuests.com



Previous Question:  Ferrofluid synhesis  General PhysicsNext Question:  Beam Splitter were is power  General Physics
Question Why magnetic field is creating around electrons ( Physics Help and Math Help - Physics Forums General Physics )
Updated: 2008-10-23 03:40:07 (22)
Why magnetic field is creating around electrons

Why magnetic field is creating around electrons when there is current in coductor? Why the magnetic field is not creating around protons?

Answers: Why magnetic field is creating around electrons ( Physics Help and Math Help - Physics Forums General Physics )
Why magnetic field is creating around electrons

Originally Posted by Ahmed Abdullah
No, motion of electrons inside the wire does not create any electric field as i have stated before.
ELECTRONS ARE MOVING WITHOUT CREATING ANY ELECTRIC FIELD INSIDE THE WIRE.
Whether stationary or in motion an electron has it's own electric field but it can be cancelled by positive charges standing nearby.
It is the moving charge (charge and electric field are not same ) which creates magnetic field -nothing more or less.
I think you are confused. Look man, moving magnet among some conductor will produce current inside the wire(electro-induction). So the magnetic field created electric field, but also the electric field can create magnetic field. So it is not even logical what u are saying, that just moving of the electrons create magnetic field.

scientist91

Why magnetic field is creating around electrons

No, motion of electrons inside the wire does not create any electric field as i have stated before.
ELECTRONS ARE MOVING WITHOUT CREATING ANY ELECTRIC FIELD INSIDE THE WIRE.
Whether stationary or in motion an electron has it's own electric field but it can be cancelled by positive charges standing nearby.
It is the moving charge (charge and electric field are not same ) which creates magnetic field -nothing more or less.

Ahmed Abdullah

Why magnetic field is creating around electrons

The origin of the magnetic field is the moving electrons but it is not confined around the electrons, though.

Ahmed Abdullah

Why magnetic field is creating around electrons

The origin of the magneic field in the wire, is the electric field which is created with motion of the electrons. But the question is, is that electric field moving?

scientist91

Why magnetic field is creating around electrons

Originally Posted by Ahmed Abdullah
Nope, it is not. Though electrons flow through the conductor it has no net electric charge. Actually for every free electron contributing in electric current there is a positively charged ion nearby. The drift velocity of the electron is constant and electrons flow through the conductor uniformly without creating any polarity.
Then how is possible only to create magnetic field around the electron? Why it is not creating around proton?

scientist91

Why magnetic field is creating around electrons

Protons are much more massive than electrons and do not move in a conductor. Since it is the motion of charge that causes a magnetic field, there is no magnetic field cause by protons.

HallsofIvy

Why magnetic field is creating around electrons

When something has a net nonzero velocity; it is in motion.

Ahmed Abdullah

Why magnetic field is creating around electrons

Originally Posted by scientist91
and is the electric field moving?
does magnetic field create around proton?
Nope, it is not. Though electrons flow through the conductor it has no net electric charge. Actually for every free electron contributing in electric current there is a positively charged ion nearby. The drift velocity of the electron is constant and electrons flow through the conductor uniformly without creating any polarity.

Ahmed Abdullah

Why magnetic field is creating around electrons

Originally Posted by jtbell
Do you mean, why do the electrons in a current-carrying wire produce a magnetic field but the protons do not? It's because the conduction electrons are moving (they have a net nonzero velocity along the wire) but the protons are not.
what is a net nonzero velocity?
and is the electric field moving?
does magnetic field create around proton?

scientist91

Why magnetic field is creating around electrons

Originally Posted by scientist91
Why magnetic field is creating around electrons when there is current in coductor? Why the magnetic field is not creating around protons?
Do you mean, why do the electrons in a current-carrying wire produce a magnetic field but the protons do not? It's because the conduction electrons are moving (they have a net nonzero velocity along the wire) but the protons are not.

jtbell

Why magnetic field is creating around electrons

Originally Posted by scientist91
Can you answer me on the first question?
No, because the question doesn't make sense, and you are apt to CHANGE the damn thing again. This is an annoying habit that you need to stop, or else the thread makes no sense.

Zz.

ZapperZ

Why magnetic field is creating around electrons

Originally Posted by ZapperZ
The 'speed' of electrons in a conductor cannot be mixed with the ones that are free. This is because electrons in a conductor can be approximated as an electron GAS, and thus, undergo collisions not just among themselves, but with the ions of the conductor. The end result is that the electrons have a CONSTANT DRIFT VELOCITY when there is an applied potential or field to the conductor.

This will not be true if these are free electrons since the Lorentz force will cause an acceleration.

BTW, you changed your question rather drastically. You should think things through a bit more before posing such questions.

Zz.
Can you answer me on the first question?

scientist91

Why magnetic field is creating around electrons

I don't understand what you're asking. Can you rephrase the question?

Sojourner01

Why magnetic field is creating around electrons

Originally Posted by Sojourner01
I don't understand what you're asking. Can you rephrase the question?
Now look the question.

scientist91

Why magnetic field is creating around electrons

The 'speed' of electrons in a conductor cannot be mixed with the ones that are free. This is because electrons in a conductor can be approximated as an electron GAS, and thus, undergo collisions not just among themselves, but with the ions of the conductor. The end result is that the electrons have a CONSTANT DRIFT VELOCITY when there is an applied potential or field to the conductor.

This will not be true if these are free electrons since the Lorentz force will cause an acceleration.

BTW, you changed your question rather drastically. You should think things through a bit more before posing such questions.

Zz.

ZapperZ

Why magnetic field is creating around electrons

Originally Posted by scientist91
That external field is the magnetic field?
No, it is the electric field created by the potential across the conductor, see my post in your other thread

Hootenanny

Why magnetic field is creating around electrons

Originally Posted by scientist91
Why magnetic field is creating around electrons when there is current in coductor?
First you shoulod realize that a an electron orbiting a circular path is equivalent to a magnetic dipole : http://hyperphysics.phy-astr.gsu.edu...ic/magmom.html

Do you know this concept ?


Why the magnetic field is not creating around protons?
Protons are far more havier than electrons and do not move in a conductor. The only movement you have in that case are the electrons in de conduction band (a concept you should also know, check the hyperphysics website). These electrons have a certain velocity called drift velocity. The cause of this movement is the applied external electrical field (or equivalently the potential) onto both ends of the conductor (like a battery). It is important to realize that electrons make this movement by feeling the change in electric field from the neigboring electrons. This variation of electric field inside the conductor is very fast (more or less the speed of light) and can be measured and used for communication purposes. It is actually this E-field variation that we use for our phones, radio's etc etc.

marlon

marlon

Why magnetic field is creating around electrons

Originally Posted by Sojourner01
Electrons have their own individual electric field. Currents exist because the electrons are responding to an external field. It is the external field, not the electric field belonging to the electrons, that is responsible for the flow of charge. Everything that responds to an external electric field has its own.

Electrons - or any particles, for that matter - do not have their own magnetic field. Magnetic fields don't work that way. What we consider a 'magnetic field' - that responsible for the Lorentz force - is a consequence of moving charges. Magnetic fields are what happens when you observe an electric field in a relativistic reference frame - from the point of view of the moving charge, the electric fields have a different geometry, and so an additional force is present.

Your suggestion that the fields are 'fixed in place' is, I suppose, true, but I wouldn't feel comfortable describing them that way. There's nothing 'fixing' a magnetic field in place; being constant in space is what a magnetic field is, at least when you have constant current. In other words, saying that the field itself could move is nonsensical; fields don't 'move'; they change in space. If you have a non-constant current, or a current-carrying object moving in space, then yes in a particular fixed position the stength and orientation of the magnetic field will change. But a magnetic field is not bound to any particular object or charge, it is what it is as a consequence of how it is generated.
That external field is the magnetic field?

scientist91

Why magnetic field is creating around electrons

Electrons have their own individual electric field. Currents exist because the electrons are responding to an external field. It is the external field, not the electric field belonging to the electrons, that is responsible for the flow of charge. Everything that responds to an external electric field has its own.

Electrons - or any particles, for that matter - do not have their own magnetic field. Magnetic fields don't work that way. What we consider a 'magnetic field' - that responsible for the Lorentz force - is a consequence of moving charges. Magnetic fields are what happens when you observe an electric field in a relativistic reference frame - from the point of view of the moving charge, the electric fields have a different geometry, and so an additional force is present.

Your suggestion that the fields are 'fixed in place' is, I suppose, true, but I wouldn't feel comfortable describing them that way. There's nothing 'fixing' a magnetic field in place; being constant in space is what a magnetic field is, at least when you have constant current. In other words, saying that the field itself could move is nonsensical; fields don't 'move'; they change in space. If you have a non-constant current, or a current-carrying object moving in space, then yes in a particular fixed position the stength and orientation of the magnetic field will change. But a magnetic field is not bound to any particular object or charge, it is what it is as a consequence of how it is generated.

Sojourner01

Why magnetic field is creating around electrons

Originally Posted by scientist91
The origin of the magneic field in the wire, is the electric field which is created with motion of the electrons. But the question is, is that electric field moving?
Technically, the field is the sum of moving components, but as each electron leaves one end of of a section of wire, another electron enters the other end, so that the net sum of these tiny fields doesn't move. Since a single electrons contribution to the total sum is so relatively small, the small variations in the electrical field are ignored. It's not practical to worry about what's going on at the atomic level when dealing with classical electical physics of currents and fields, which involve huge numbers of moving electrons.

Note that free electrons don't flow smoothly. They move at very high speed, almost randomly in all directions, occsionally being captured by atoms causing the release of a different electron. The movement is almost random, but there is a net flow of electrons when there is current. This net flow is extremely slow compared to the actual speed of the free moving electrons.

Jeff Reid

Why magnetic field is creating around electrons

Originally Posted by scientist91
The origin of the magneic field in the wire, is the electric field which is created with motion of the electrons. But the question is, is that electric field moving?
There is no electric field to move.

Ahmed Abdullah

Why magnetic field is creating around electrons

So the magnetic nor the electric field are attached to the electrons right? They are positioned in one place, right?

scientist91

Previous Question:  Ferrofluid synhesis  Physics Help and Math Help - Physics Forums  General PhysicsNext Question:  Beam Splitter were is power  Physics Help and Math Help - Physics Forums  General Physics

- Source: Why magnetic field is creating around electrons Physics Help and Math Help - Physics Forums General Physics
- Previous Question: Ferrofluid synhesis Physics Help and Math Help - Physics Forums General Physics
- Next Question: Beam Splitter were is power Physics Help and Math Help - Physics Forums General Physics