ELECTRONS

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It has been a few years, well decade or two since I was actively seeking this kind of knowledge, but please enlighten me. When I was young electrons flowed. As I got older, electrons were no longer necessarily a particle, possibly a wave, holes flowed instead of electrons, etc. Are we back to electrons as a particle that actually move, from one end of a wire to the other?
 
Strathead said:
It has been a few years, well decade or two since I was actively seeking this kind of knowledge, but please enlighten me. When I was young electrons flowed. As I got older, electrons were no longer necessarily a particle, possibly a wave, holes flowed instead of electrons, etc. Are we back to electrons as a particle that actually move, from one end of a wire to the other?
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Has not changed much since the wave nature of quantum particles was first introduced.
Sometimes they behave like a wave (but a wave carrying a discrete amount of energy), sometimes their behavior is most easily understood and described as particles.
And hole motion only comes into play when discussing semiconductors. In a metal it is definitely the electrons that move.
 
My favorite more easily demonstrable analogy is to line up to coins in a straight line on the table, all touching each other. Then take an 11th coin and flick it into the coin one the end of the line. The coin on the other end moves instantly, the energy transferred through the line of coins at the speed of light. But how FAR it moves has everything to do with the force at which the 11th coin was flicked into the lineup, the equivalence of voltage in the electron movement, mitigated by any friction of all of the coins against the table top, the equivalent of resistance.
 
Jraef said:
My favorite more easily demonstrable analogy is to line up to coins in a straight line on the table, all touching each other. Then take an 11th coin and flick it into the coin one the end of the line. The coin on the other end moves instantly, the energy transferred through the line of coins at the speed of light. But how FAR it moves has everything to do with the force at which the 11th coin was flicked into the lineup, the equivalence of voltage in the electron movement, mitigated by any friction of all of the coins against the table top, the equivalent of resistance.
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10 coins, not "to" coins...
 
Jraef said:
My favorite more easily demonstrable analogy is to line up to coins in a straight line on the table, all touching each other. Then take an 11th coin and flick it into the coin one the end of the line. The coin on the other end moves instantly, the energy transferred through the line of coins at the speed of light. But how FAR it moves has everything to do with the force at which the 11th coin was flicked into the lineup, the equivalence of voltage in the electron movement, mitigated by any friction of all of the coins against the table top, the equivalent of resistance.
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I think the single rail car pushed into the tunnel full of them analogy works better.
 
Besoeker said:
I think the single rail car pushed into the tunnel full of them analogy works better.
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Harder to demonstrate in front of someone though...

I've also used a Newton's Cradle...
Newtons_Cradle_Small04_30.gif
 
fmtjfw said:
Picard:What do you think our chances are of getting out of this alive?
Data: Approximately 1 in 898.985337438205.
Picard: Approximately.
Data: (Mildly surprised look) Yes, captain.
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Is that for real? It was for sure in the first Star Trek. I made up the number, of course.
 
electrons

electrons

If i have a #12 copper wire pulling 10 amps and a # 12 wire pulling 4 amps both 120 volt . are the electrons moving faster in the wire with 10 amps ? does the 10 amp wire have more electrons flowing ?
 
domnic said:
If i have a #12 copper wire pulling 10 amps and a # 12 wire pulling 4 amps both 120 volt . are the electrons moving faster in the wire with 10 amps ? does the 10 amp wire have more electrons flowing ?
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The number of free (able to move to conduct current) electrons in the wire is proportional to the mass of the wire. The number of electrons passing through a given cross section per unit time will be proportional to the current.
So the product of the number and the speed will increase with the current.
I have not seen an authoritative source, but my gut feeling is that it is the speed which increases as you increase the current in a given conductor.
The moving electrons then "run into" the stationary electrons (not free to move) causing both the IR voltage drop and the heating.

Tapatalk!
 
ggunn said:
It's also important for stock trading. Trading computers have a minimum length of CATx cable they must use to make things "fair". "Fair" in that context is a laughable concept to the rest of us. end rant
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No they don't. The actual crazy now is the miles of coiled fiber to simulate distance so your trade gets to Chicago, NY and Philly at exactly the same time even though you are in say Boston.

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Actually, if ggunn is talking about the same thing I saw described on 60 Minutes, this is a special exchange in Canada which delays outbound information on orders and transactions so that the high velocity traders do not have time to squeeze their orders in ahead of the original order on both the local exchange and distant exchanges.
The idea is not to make up for the transit time, since that potentially affects all parties equally, but to allow multiple trades to take place before the "outsider" collocated at the exchanges can react.

Tapatalk!
 
domnic said:
If i have a #12 copper wire pulling 10 amps and a # 12 wire pulling 4 amps both 120 volt . are the electrons moving faster in the wire with 10 amps ? does the 10 amp wire have more electrons flowing ?
Click to expand...
From my calcs about:
0.006645669 in/sec
and
0.002658268 in/sec
respectively.
 
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