Do Electrons Physically Move in a Conductor or Just Align When Voltage Is Applied?

someone help me,do electrons actually move or they simply align in one direction when a voltage is applied across a conductor?if they move is there any effect of their movement in a conductor?and if they not move why we pin the term drift velocity?

Yes charge moves: I = Q/t or coulombs/sec drift velocity. The effect of their movement? You mean like generating a magnetic field, and/or heat, and/or skin effect (in the case of high frequency alternating current)? Is that why you are asking?

I think there is a bit more to this question:
My limited understanding is that electrons do not flow at light speed along a conductor but the effect of the current flow allows signal to pass at near light speed along conductors.
I hope someone can say a little more.

Well, I did a bit of research on this, and discovered that my comment about _drift velocity_ is may be incorrect. Some, better informed sources:

* http://van.physics.illinois.edu/qa/listing.php?id=3341
* http://www.sciforums.com/Speed-of-the-electrons-t-5527.html

Hi

No is the short answer to this not all conductors have the same level of conduction

A lot of people think of electron flow as electrons moving along a wire freely like cars go down a highway.
Actually, it works a little differently. Any conductor (thing that electricity can go through) is made of atoms. Each atom has electrons in it. If you put new electrons in a conductor, they will join atoms, and each atom will spit out an electron to the next atom. This next atom takes in the electron and spits out another one on the other side.

For a more thorough explanation see


http://www.allaboutcircuits.com/vol_1/chpt_1/2.html


For more details on thermionic emission , different to flow of electrons through conductors see the following

http://www.ampbooks.com/home/tutorials/lesson-001/

See also

http://www.cedengineering.com/upload/Introduction to Electron Tubes.pdf

What about the fact that metals, especially the more highly conductive metals like copper, silver and gold, have "free electrons" -- called that because they wonder freely in the material. So, perhaps it's not always the case that an electron is kicked off an atom. I think the actual driving (and equalizing) force (or factor) is the electric field, and the need to keep it in balance. An electric field is applied across a conductor and due to the attractive and repulsive forces between the field and the electrons (or charge carriers [such a _holes_ in a semiconductor, or ions in a plasma, or, what the heck, positrons in whatever system they might exist]) are propelled (or compelled) by the imbalance. Where the charge carrier comes from is immaterial. It might be an electron stripped from an atom or it might be a free electron accelerated by the field.

What is a free electron Steve?? if it hastnt been emitted by an atom, uhm periodic ,table maybe

Noble gas structure!! Hmmmmm interesting

Which atoms are the most unstable Steve ??

For more information Steve And back to basics me old mucker Standard 8 in Johannesburg Jolly old Rotten South Africa where education is just so diabolical ,there you will find my dear friend that we studied this back in the early 70s And education which Britain has so dearly insulted for decades and where degrees are not recognized by Britain until of course, you attend Goldsmiths College based in Lewisham and there sitting in the class to this very day You will find people that cannot add up , cannot do fractions , cannot factorise , do not know about SI standards, never mind periodic tables , but are studying electronics and all manor of assorted subjects

Whilst dear old jolly old britain with record debts and record companies going bust then proclaim tut tut tut , The rest of the worlds education inclusive South Africa where we did beat the the poor blacks yup !! plus ball the other political scandal ha hooo , turned on us like no tomorrow whilst we manufactured our own oil stood in the face of terrorism now strongly evident in britain ,ha ha , and whoopsy would you just believe this too are seeing riots escalate just as we did In south africa back in the 70's , now the 80's and the 90's In britain as well

Oh dear calamity !! shucky wucky Of course i suppose thats our fault as well hmmm Yes ok !!



Companies refuse to invest and those that do What do they do yes my jolly od fruit They shiut them down curtisy none other than the Banks of england TRUE !!! 100 Precent TRUE all of it !!

Not that Goldsmiths College is a bad college just that educational standards in Britain my dear friend ,thanks to Governments both past and present have been ignored as to have training schemes for decades They don’t force people to do propriety subjects and what have they done stuffed the country up

Same old argument all over again !! Well, well, well Apart from what else Steve firing and making teachers redundant left right and center just like they normally do What eles Steve Closing schools left right and centre

Where eles Steve Universities, Dont need the maths teachers after year 1.5

Rubbish !! They do !!

Good isnt it !! What does this do for Britain ?? Turns this country into a third world country Steve !! Thats all it does !!



Still want to vote for conservatives do we ??

Sum this up for you yet does it !! OH Yah ,, Now its comming out isnt it !!

Oh Ive been waiting for this day for so long


Ho Hum ha ha ha
http://www.webelements.com/

Definitely have to have a sense of humor with this

Whoopsey !!

The atom will gain or loose electrons until it has the same count of electrons as the nearest noble gas. Noble gas electron configurations are configured "stable". This type of configuration is "desired" in both ionic and covalent bonding.

Let's take Lithium and Fluorine for example.

Lithium is closest to Helium. If it looses 1 electron, it can have the same configuration as He.
Fluorine is closest to Neon. If it looses 1 electron, it can have the same configuration as Ne.

Hence, Lithium looses an electron becoming a positive cation, and Fluorine gains an electron, becoming a Fluoride anion.

As a result:
Lithium Fluoride is formed.

--------------
Had lithium attempted to gain electrons, it would need seven extra electrons to become a Lithide anion. Such an ion doesn't exist.

Had Fluorine attempted to loose electrons, it would need to loose seven electrons to become a Fluorium cation. Such an ion doesn't exist.
------------
Hydrogen is unique because it can both gain and loose electrons in ionic bonding:

If Hydrogen looses its electron, it becomes a hydrogen ion, which is a cation. It now has the electron configuration of the "noble gas Zeron", meaning it has no electrons and is just a free proton.

If Hydrogen gains an electron, it becomes a hydride ion, which is an anion. It now has the electron configuration of the noble gas Helium.

--------------------
Helium can also become an ion. Its name ends in "-ium" because it was actually discovered on Earth as its positive ion. The helium ion has the electron configuration of Zeron. Such an ion is 2 protons and 2 neutrons in a nucleus. This is termed an alpha particle. It is the result of radioactive decay. Later, it eventually finds two stray electrons and becomes the Helium gas we use for balloons and blimps.

Once Helium is a complete atom, it is extremely difficult to return it to the alpha particles, since it already has a stable configuration.

Co Valent bonding .... Strike a bell does it !! Outer electrical orbit !! hmmm

Must remember this !!

I had a similar question like this & I'll tell you how it was explained to me.

Any type of circuit is obviously hooked up to a battery & inside the battery are the electrons. And we should all know that electors have a negative charge (e-). So inside the battery, these negative electrons are extremely attracted to the positive charge of the (+) positive terminal, which can be see on almost any battery, & they are repelled by the negative terminal (-). So when the battery is connected to something that allows current to flow, like a copper wire, the electrons flow from negative to positive, hence why the electron is negative.

Now before I get any further, the statement above is not ALWAYS TRUE. Current flow can go from positive to negative terminals when a batteries are hooked up to something with a HUGE (bigger than that of the battery) voltage difference. This is an example of battery charger (rechargeable batteries.)

The chemical reaction is what pushes the electrons inside toward the negative end, because the electrodes at the two ends are made of different materials, which have different chemical stabilities. So overall, electrons flow AROUND the circuit, toward the negative end inside the battery, pushed by the chemical reaction, and toward the positive end in the outside circuit, pushed by the electrical voltage.

And to answer you question about drift velocity of electrons I will tell you depending on what type of physics you're studying it really just depends. Electrons DO MOVE, but many people think that it is so negligible it's better off teaching people they don't. You have to have view OHM'S LAW at a microscopic level. It's very interesting stuff, but if you're taking classical physics (calculus-based) they should teach you this.

If you want to learn more about Vdrift of electrons go here:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmmic.html

The outer electrons in a metal are so loosely bound to the atom that they tend to move around -- this is called the "Free Electron" model:

* http://en.wikipedia.org/wiki/Free_electron_model

Also, I'm not talking about Nobel Gases (which aren't metals, at least not at or near STP). BUT, there are free electrons in an ionized Nobel Gas (i.e. Plasma) -- that's essentially what _ionized_ means, some or all of the electrons have been separated from the atom, leaving it with a positive charge because there are no longer enough elections to balance out the charge of the protons.

I didn't much more than the first paragraph -- so can't respond to any more than that

...and what does any of this have to do with the original topic: the motion of electrons in a conductor?

Dear Mark,

Are you a spamming bot?
I would sugest you studing some solid state phisics and/or statistical phisics before giving such an uninformed reply.

This MIT OCW lecture notes explain it quite nicely
http://ocw.mit.edu/courses/electrical-enginee...and-circuits-fall-2005/lecture-notes/lec3.pdf

http://web.mit.edu/8.02t/www/materials/StudyGuide/guide06.pdf