The Electron Theory
organ
Posts: 4,969
When I was in college, there were quite a few interesting stuff I couldn't forget from the electronics/electrical theory classes.
I don't know how much farther science has gone since that time when it comes to the study of electrons, but here's what the prof. told us back then.
He said that electrons are everywhere, and that there is a camp who believe they don't travel through cables at all.
A copper wire will have electrons within the copper. So when a circuit is comppleted, these electrons, instead of flowing from one end to the other, just "excite" their neighbours (chain reaction type thing). So one would vibrate very intensely, and the energy from that would make the electron beside it vibrate, and so on. So the conductivity of a conductor may tell us how much of them are present or how much that material is impeding the exitement.
I found this theory very interesting. So if we put that into our 2ch rigs, it would mean that the electrons embedded into our copper, silver, etc wires behave in their own way. It's not that the electrons are "happy", "sad", or "frustrated";), they just have a different level of exitement in different conductive materials.
Not sure what is known about electrons at the present time. Has this theory been proven or taken out?
I don't know how much farther science has gone since that time when it comes to the study of electrons, but here's what the prof. told us back then.
He said that electrons are everywhere, and that there is a camp who believe they don't travel through cables at all.
A copper wire will have electrons within the copper. So when a circuit is comppleted, these electrons, instead of flowing from one end to the other, just "excite" their neighbours (chain reaction type thing). So one would vibrate very intensely, and the energy from that would make the electron beside it vibrate, and so on. So the conductivity of a conductor may tell us how much of them are present or how much that material is impeding the exitement.
I found this theory very interesting. So if we put that into our 2ch rigs, it would mean that the electrons embedded into our copper, silver, etc wires behave in their own way. It's not that the electrons are "happy", "sad", or "frustrated";), they just have a different level of exitement in different conductive materials.
Not sure what is known about electrons at the present time. Has this theory been proven or taken out?
Post edited by organ on
Comments
-
When I was in college, there were quite a few interesting stuff I couldn't forget from the electronics/electrical theory classes.
I don't know how much farther science has gone since that time when it comes to the study of electrons, but here's what the prof. told us back then.
He said that electrons are everywhere, and that there is a camp who believe they don't travel through cables at all.
A copper wire will have electrons within the copper. So when a circuit is comppleted, these electrons, instead of flowing from one end to the other, just "excite" their neighbours (chain reaction type thing). So one would vibrate very intensely, and the energy from that would make the electron beside it vibrate, and so on. So the conductivity of a conductor may tell us how much of them are present or how much that material is impeding the exitement.
I found this theory very interesting. So if we put that into our 2ch rigs, it would mean that the electrons embedded into our copper, silver, etc wires behave in their own way. It's not that the electrons are "happy", "sad", or "frustrated";), they just have a different level of exitement in different conductive materials.
Not sure what is known about electrons at the present time. Has this theory been proven or taken out?
Tubes spoil this and that "damn hole theory". How do you excite electron
neighbors across a gap in a vacuum between cathode and anode?
Or how do you get "holes" (lack of electrons) to jump the gap?
Sounds like modern economics to me. They seem to have based banking
standards on "holes" too."The legitimate powers of government extend to such acts only as are injurious to others. But it does me no injury for my neighbour to say there are twenty gods, or no god. It neither picks my pocket nor breaks my leg." --Thomas Jefferson -
http://en.wikipedia.org/wiki/Electric_current
The "free" electrons move easily around in a metal lattice because the valence band of various metals is only partially filled. Therefore the electrons are free to jump from one atom to another since there is empty valence bands in neighboring atoms. One applies an electric field and this gives the "incentive" for electronics to move more easily. -
The "outermost" electrons of metals are sort of diffuse; it's what makes metals good conductors of electricity. Metal atoms share a 'sea' of valence electrons. It's actually given as a reason for the shiny-ness of metals (you could look it up).
The electrons do move, but the drift velocity is actually pretty leisurely. The electro(n)motive force (EMF); which is what makes 'em move, propagates at the speed of light (well, technically the speed of light in the medium in question).
It's a little weirder than that, microscopically, because electrons exhibit both wave and particle behavior... but in discussions of electricity, it's generally best, and easiest, to think of them as particles. It doesn't help that 'conventional current' notation, which was developed before the physics of electromagnetic radiation was very well understood, envisions current flowing from plus to minus (the opposite of the flow of electrons). -
I've often wondered about similar things.
When you connect a battery to a circuit, how does it know that each component will drop a certain voltage creating a specific current? Well, it doesn't and doesn't need to.
When you talk about electrons vibrating and transferring this along, you're describing superconductors. In a superconductor, there are no collisions between the electrons and the lattice. When one electron moves out of place, the charge imbalance causes other electrons to move in response. The charge travels a lot like a sound wave.
In a normal conductor, there are collisions with the lattice.
The one thing I want to know is this:
If I have a wire going to the moon and back and then connect it to a battery, does the drift current propagate down the wire at the speed of light or is it instant at all points?
Damn you quantum mechanics. What makes it even worse is when you realize electrons have a wavefunction to describe them. Superconductors and electron microscopes wouldn't exist without the wavefunction. What this wavefunction implies is that each electron has an influence that expands into ALL of space but has different probabilities at different points. So basically, if two circuits are very close to each, an electron can just disapear from one circuit and appear in the other.
I suggest you do not pursue the matter further, as quantum wave mechanics is beyond weird and not reasonable(this means you can't explain why it does what it does).
p.s. When referring to semiconductors, make note the 'holes' and 'charges' are majority carriers. You'll always see electrons and holes propagating, but the semiconductor type(N or P) tells you which trumps the other in volume. So, P-type semiconductors are not strictly 'holes' moving around. Make note I'm not saying anything here to anyone, just specifying that transistors have majority AND minority carriers.
If you want electron weirdness, look up (Josephson junction) and (SQUID). They make use of supercurrents. Don't can't call it a current, it's too super for that. In a transistor, charges move individually. In a josephson junction, pairs of electrons are transmitted. So the current is 2e instead of e. The junction has other properties, like creating an AC supercurrent when a DC potential is applied. This is used to measure voltage extremely accurately. Read: world's most accurate voltmeter.
Also, a pair of these junctions can be used to measure extremely weak magnetic fields thanks to the wave nature of electrons.
Electrons are neat little fermions. Sorry for the long and mostly useless post. -
The one thing I want to know is this:
If I have a wire going to the moon and back and then connect it to a battery, does the drift current propagate down the wire at the speed of light or is it instant at all points?
mhardy answered this already... the average velocity of the electronics is called the drift velocity and it is quite slow. However, the effect of one electron inducing the other to move travels at near the speed of light. Specifically, the speed of light divided by the square-root of the material's dielectric constant. This is called a signal transient response, and it is what RF engineers like to study. -
When I was in the Navy's aviation electronics school they taught us holes flow. Every 28 days.Lumin X1 file player, Westminster Labs interconnect cable
Sony XA-5400ES SACD; Pass XP-22 pre; X600.5 amps
Magico S5 MKII Mcast Rose speakers; SPOD spikes
Shunyata Triton v3/Typhon QR on source, Denali 2000 (2) on amps
Shunyata Sigma XLR analog ICs, Sigma speaker cables
Shunyata Sigma HC (2), Sigma Analog, Sigma Digital, Z Anaconda (3) power cables
Mapleshade Samson V.3 four shelf solid maple rack, Micropoint brass footers
Three 20 amp circuits. -
Thanks a lot for the clarification. It makes more sense to me now, but after reading your replies, I may have more questions tha before. I will do more reading on electrons.
I hope youtube have some nice explanations and visuals to make it easier.
Thanks again -
unfortunately quantum mechanics is one of those things (IME and IMNSHO) that makes less and less intuitive sense the more one learns about it. One needs to trust the mathematics (and the statistics), I guess.
-
It's not a real theory, it's purely based on statistics mechanics. Hence why we refer to interpretations of the theory, aka, Copenhagen.
You can't say what an individual electron is doing, only the averages of what will happen if we try the experiment lots of times. -
well... as our buddy Herr Doktor Heisenberg would say: we can tell you the velocity of an electron or its location ; but not both. He wasn't totally certain about that, though.
A favorite nerd bumpersticker: Heisenberg may or may not have slept here -
This is for mhardy as it doesn't really belong on this forum:
The position - momentum uncertainty relation (~h) can be shown as a consequence of the wavenature alone through fourier analysis. We need many cycles for the wavelength to be known precisely. As you narrow a position, you lose precision in the wavelength(which de Broglie showed is directly related to the momentum of the particle).
Luckily, Heisenberg also stated that the time - energy relation obeys the same uncertainty. Big it up for my man Heisenber on that one.
Almost how symmetry has given meaning to conservation laws, Fourier analysis leads directly to the classic uncertainty relationship. -
:-)
Not my strong suite, though -- as you can tell by my semi-inane posts (I'm a biochemist, not a physicist)
