How to pass the electrons through the wire?

[alpha2cen]

It's well known electrons pass through the wire.

But how does one electron move form this part of the wire to that end of it is not well known.

One of them is this .

We think it as a water pipe, one water molecule goes into this part of the pipe and another molecule comes out at the other part of pipe.

And the velocity is very fast.

It is close to light speed.

Is this concept right?

[Danijel Gorupec]

The analogy with water pipe is okay enough.

 

In water pipe: one molecule is forced into pipe, the disturbance spreads rapidly along the pipe (at speed of sound in the water), and another molecule drops out on the other end.

In wire: one electron pops in, the disturbance spreads rapidly along the wire (at speed close to the speed of light), and at the other end an electron pops out.

 

The important thing is that electrons move very slowly, but disturbances move fast.

 

But why do you say that this is not 'well known'? Do you mean 'in general population'?

 

 

 

[alpha2cen]

 

But why do you say that this is not 'well known'? Do you mean 'in general population'?

 

I don't know detail mechanism.

I thought electron movement in the vacuum tube is not so fast.

But telecommunication signal is transfered very fast, almost light speed.

Are there any detail mechanisms about this?

[Danijel Gorupec]

In the vacuum tube elctrons move at relatively high speeds. However in the wire, it is much different - the wire is already completely populated with electrons. If you put one extra electron inside, others will fill the jam and will quickly readjust their positions. Electrons won't actually move much, just a few nanometers to reach new equilibrium. But the disturbance will quickly spread along the wire (like a wave).

 

Electrons 'feel' other electrons because of the negative charge they posses. That's why they don't like 'standing' too close to each other.

 

When a signal is transferred from point A to point B in a telecommunication wire, it is not that electrons are moved from point A to point B, but instead a disturbance is generated at point A, then the disturbance spreads along the wire and is finally detected at the point B.

 

The above is very simplified. Other people may provide 'harder details'.

[alpha2cen]

 

The above is very simplified. Other people may provide 'harder details'.

 

Then in the copper how electron current flow?

e: electron

 

e............e.............e...............e...............e............e...........e................e...............e............e..... /////..................opposite site of the Earth.................//////...........beginning point

----------->---------->.........................................................................................................................................................................................................................------>

Why is it so fast?

Which one is correct ?

1) They (free electrons) move fast originally, electro current is defect of their current.

There is a river. we throw a leaf in the stream.

2)They don't move originally. When we give them electric excess, they move in order to go to the stable state.

3) Others, other theory?

[swansont]

It's like a train. You push or pull on one end and the whole train begin to move, because each car interacts with the one next to it. The train may move slowly, but the speed at which the "pushing" acts is fast, i.e. the 1000 m long train may move at just 1 m/s, but the time delay between starting to push and the far end starting to move is much shorter than 1000 seconds.

[alpha2cen]

It's like a train.

 

If we see it on the macroscopic scale , it is right .

But when we see it on the microscopic scale, we can see other scenery.

How one electron hit other electron --> other electron --> final electron...??? very fast.

There are huge amount of electrons in the copper.

How do the rest of electrons know some electrons come in?

[swansont]

Electrons push each other via the electromagnetic interaction, which proceeds at the speed of light.

[alpha2cen]

When an electric wire cut the magnetic lines, electric current would flow.

There is no electron come into the wire.

But current flow.

 

Make circuit like this.

Closed circuit which is composed of vacuum tube and copper coil.

We move it in the big magnetic bar.

Then, electric current would flow.

There is no electron input.

How would you explain the electron flow from the cathode to the anode of the vacuum tube?

I think this flow is same as the flow inside the copper wire .

Similar phenomena is occurring in the very long fluorescent lamp for advertising.

So I think the current inside the copper is not so slow.

[swansont]

There are electrons in the wire already, and a small fraction (but a huge number) are free to move around, as they are in the conduction band. You don't need to add any from outside the system.

[alpha2cen]

I confuse with applied voltage.

In the vacuum tube the operating voltage should have be very high.

The current in the copper wire is proportional to voltage.

In order to operate vacuum tube, very high speed electric current is required.

And then, communication speed through copper wire is not electron current but electromagnetic wave transfer speed.

Thank your for answering.

[steevey]

It's well known electrons pass through the wire.

But how does one electron move form this part of the wire to that end of it is not well known.

One of them is this .

We think it as a water pipe, one water molecule goes into this part of the pipe and another molecule comes out at the other part of pipe.

And the velocity is very fast.

It is close to light speed.

Is this concept right?

 

What tends to happen with metals, especially transition metals is that when the electrons are given enough of a type of energy, they are released from their current bonds, but cannot escape the totality of the copper as to form a plasma, so what an electron does is try to go to the next atom, or whatever atoms is closest. The reason an electrical "current" forms is because as soon as that atom loses an electron, it wants one back, so when you have all the atoms losing electrons while the electrons aren't completely free, it allows the electrons to be carried along the wire. But, if the wire runs into something where there can no longer be a current, the electrons can't go go forward, which means the electrons behind it also can't, which means no more atoms are losing electrons.

 

And the reason electricity travels so efficiently though metals is because in metals, the electrons are more aligned with each other and close to each other, much like in the picture, where as in something like sulfur, the atomic structures are more complex and over the place, and is less dense.

Edited December 19, 2010 by steevey

[swansont]

In a conductor the electrons are free to move within the lattice and not bound to any individual atom. It's the conduction band, and is already populated with electrons. If you need to add energy to get the electron into the conduction band, it's a semiconductor or an insulator.

[lemur]

When an electric wire cut the magnetic lines, electric current would flow.

There is no electron come into the wire.

But current flow.

I think a good way to look at it would be to see the electrons like gaseous particles in the wire which are variously pressurized or depressurized by the negative or positive pole of a magnet, respectively. Then, the de-pressurized area moves like a wave through the conductor, for some reason. I don't get why it would become mobile except that the rest of the wire isn't insulated as much as it is insulated from its surroundings, so the energy has nowhere else to go, really, except down the wire, I think.

 

Coincidentally, I was just trying to read A Survey of Physical Theory by Max Plank and the following quote is from page 5, which seems relevant:

. . . in which category may the laws of motion of electrons be placed? Perhaps at first sight one would say they belong to electro-dynamics, since in the theory of electrons ponderable matter plays no part. But let attention be directed simply to the motion of free electrons in metals. There it will be found, from a study of the investigations of H. A. Lorentz, that the laws themselves fit in far better with the kinetic theory of gases than with electrodynamics. . .

Thus, Plank seems to be saying that electrons in a conductor behave like gas particles. Normally, I wouldn't bother typing out a quote like this but I got excited that I just read this and it came up.

Edited December 20, 2010 by lemur

[alpha2cen]

I think a good way to look at it would be to see the electrons like gaseous particles in the wire which are variously pressurized or depressurized by the negative or positive pole of a magnet, respectively. Then, the de-pressurized area moves like a wave through the conductor, for some reason. I don't get why it would become mobile except that the rest of the wire isn't insulated as much as it is insulated from its surroundings, so the energy has nowhere else to go, really, except down the wire, I think.

 

Do we think this electromagnetic induction as one of the electric current flow phenomena ?

Unseen magnetism in the copper is doing important rule in the electric current flow.

When copper wire cut the magnetic lines, the electrons in the copper wire are released form the restriction of the copper atom magnetism, is it right?

This released electron concentration difference in the line makes electron voltage deviation,and electric current flow.

The electric flow amount is proportional to magnetic line cutting speed and magnetic field.

[swansont]

When copper wire cut the magnetic lines, the electrons in the copper wire are released form the restriction of the copper atom magnetism, is it right?

This released electron concentration difference in the line makes electron voltage deviation,and electric current flow.

 

No, there is no "restriction of the copper atom magnetism." Electrons in the conduction band are free to move within the metal. Motion through a magnetic field looks like an electric field in the rest frame, and that exerts a force on the electrons.

[alpha2cen]

Motion through a magnetic field looks like an electric field in the rest frame, and that exerts a force on the electrons.

Then.

Why the electrons in the copper wire move when the wire cuts the magnetic line fast?

Which one makes the electron driving force?

Think over at the atomic level.

At the super conductor the magnetism is almost zero.

[swansont]

Then.

Why the electrons in the copper wire move when the wire cuts the magnetic line fast?

Which one makes the electron driving force?

Think over at the atomic level.

At the super conductor the magnetism is almost zero.

 

Because motion through a magnetic field looks like an electric field in the rest frame (i.e. the wire), and that exerts a force on the electrons.

[alpha2cen]

"Because motion through a magnetic field looks like an electric field in the rest frame (i.e. the wire), and that exerts a force on the electrons."

Others said,'First, charge is separated, and an electric field is created.

Edited December 21, 2010 by alpha2cen

[TonyMcC]

When an electric wire cut the magnetic lines, electric current would flow.

There is no electron come into the wire.

But current flow.

 

Make circuit like this.

Closed circuit which is composed of vacuum tube and copper coil.

We move it in the big magnetic bar.

Then, electric current would flow.

There is no electron input.

How would you explain the electron flow from the cathode to the anode of the vacuum tube?

I think this flow is same as the flow inside the copper wire .

Similar phenomena is occurring in the very long fluorescent lamp for advertising.

So I think the current inside the copper is not so slow.

In a typical cathode ray tube (CRT) electrons are emitted from the cathode because it is held at a high temperature by a filament heater.

They have a negative charge and in the absence of any other influence would form a space cloud of electrons around the cathode.

However a very large positive potential attracts the electrons up the tube towards the screen. The tube contains a vacuum so that there is nothing for the electrons to strike. Because of the very high positive potential and the ease of movement through the vacuum the electrons rapidly accelerate and may reach 1/10 the speed of light before striking the screen.

[swansont]

"Because motion through a magnetic field looks like an electric field in the rest frame (i.e. the wire), and that exerts a force on the electrons."

Others said,'First, charge is separated, and an electric field is created.

 

"Others" are incorrect. I pointed out that electrons in the conduction band are free to move within the material. They are not bound to a particular atom.

[alpha2cen]

"Others" are incorrect. I pointed out that electrons in the conduction band are free to move within the material. They are not bound to a particular atom.

 

I knew it today by accident.

Have a look this site.

http://www.attanolea...ler.selectVideo

Edited December 21, 2010 by alpha2cen

[swansont]

I knew it today by accident.

 

?

 

Have a look this site.

http://www.attanolea...ler.selectVideo

 

I'm not sure what your point is. Nothing in the video contradicts what I have said.

 

Yes, it's called the Hall effect, and yes, it's an application of Faraday's law. The changing magnetic field gives rise to an electric field when you transform into the frame of the conductor, which is what drives the current.