Electrons and color codes

russ_hensel

Joined Jan 11, 2009
825
But protons don't move (other than brownian motion), the positive charge is the absence of the electron that has moved on. Unless we are talking antimatter or some other exotic situation, only the electrons move. Holes are just a concept that makes the math easier.
I think you are limiting yourself to metalic conductors and semiconductors. The protons at cern, do move and fast. In solutions the current may be carried by ions, and the predominate ones may not be negative.

Arguing that current flows in the direction that electrons would flow if the are the only chage carrieries is not too different from arguing that since electrons are the most common charge carrieries they should be defined as positive, not negative. Direction of current flow is a convention, and confusion comes from messing with it. If you want to try to change a convention that makes even less sense then lets get after the qwerty keyboard.

I hope no one take offense, this is sort of fun to argue about, and I like to be on the correct side, but mostly this is not an important issue.

Keep in mind that x is horizontal, and y is verticle (sp ) and if you mess with it too much the cross product reverses direction.
 

beenthere

Joined Apr 20, 2004
15,819
Convention usually is arbitrary at the moment of inception, but becomes the definition of whatever event it was applied to thereafter. So, while labeling battery terminals "positive" and "negative" was simply a convention to allow researchers to use the same polarity without confusion, it is now the definition of the polarity of any voltage.

As the convention was firmly established at the time of the Millikan oil drop experiments, it serves to define the nature of electric charge carriers and their polarity. Most simply stated, electrons carry charge, and it is negative.

Do recall that James Clerk Maxwell did his work more than 30 years before Millikan. There was no defined charge carrier - moving charges could be demonstrated, but the mechanism was more like phlogiston than particles.

As electrons have always been the charge carriers, how is direction of charge flow a convention?

In water, ions are the apparent carriers. The ones with extra electrons carry those electrons to the positive electrode. The ones missing an electron go to the negative electrode to receive one. The transport mechanism is involved with shuttling electrons back and forth to balance charge.
 

thingmaker3

Joined May 16, 2005
5,084
Without looking them up it is apparent that if you have a current flowing in the reverse direction and use maxwells equ to determine the magnetic field, you will need a new minus sign, or the magnetic field will be in the wrong direction.
No sign change is needed. One simply defines directions inversely. +3 Amps is +3 Amps regardless of whether we call it "hole flow" or "electron flow." -2 Amps is -2 Amps, regardless of whether we call it "proton flow" or "mu-metron flow."
Do I need to drag out the specific equations!?
If it will help you understand what is happening, then by all means do bring them out.
Arguing that current flows in the direction that electrons would flow if the are the only chage carrieries is not too different from arguing that since electrons are the most common charge carrieries they should be defined as positive, not negative.
Indeed. It is a poTAYto poTAHto argument. Both models are valid.
I hope no one take offense, this is sort of fun to argue about, and I like to be on the correct side, but mostly this is not an important issue.
:D Are you related to Ratch?
 
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digitalmind

Joined Mar 7, 2009
30
I'm lost. I'm asking my tutor for advice. Or perhaps I'll "get it" one day after many years of experience and trying both conventional and electron flow texts.
 

russ_hensel

Joined Jan 11, 2009
825
Convention usually is arbitrary at the moment of inception, but becomes the definition of whatever event it was applied to thereafter. So, while labeling battery terminals "positive" and "negative" was simply a convention to allow researchers to use the same polarity without confusion, it is now the definition of the polarity of any voltage.

As the convention was firmly established at the time of the Millikan oil drop experiments, it serves to define the nature of electric charge carriers and their polarity. Most simply stated, electrons carry charge, and it is negative.

Do recall that James Clerk Maxwell did his work more than 30 years before Millikan. There was no defined charge carrier - moving charges could be demonstrated, but the mechanism was more like phlogiston than particles.

......

So far this seems to be pretty much my point. It was long ago agreed that current flows from plus to minus. Current direction does not have to agree with charge flow direction. For a displacement current there is no charge flow at all ( Maxwell again )

For the rest of what you say I am not sure if you are supporting what I say or not, except I will say again that electrons are not the only charge carrieries so they have not always been THE charge carrieries.
 

russ_hensel

Joined Jan 11, 2009
825
No sign change is needed. One simply defines directions inversely. +3 Amps is +3 Amps regardless of whether we call it "hole flow" or "electron flow." -2 Amps is -2 Amps, regardless of whether we call it "proton flow" or "mu-metron flow."If it will help you understand what is happening, then by all means do bring them out.Indeed. It is a poTAYto poTAHto argument. Both models are valid. :D Are you related to Ratch?
See attached pdf

Looked at some of his ( Ratch ) post, perhaps I should invite him to be a friend.
 

Attachments

thingmaker3

Joined May 16, 2005
5,084
See attached pdf
This law ( sorry I could
not find my e and m text ) is I think closely related to the right hand rule for the magnetic field around a
wire.
Check the fine print in your textbook. You will find it specifies conventional current flow. I was taught "left hand rule" because I was taught electron flow.

Poh TAAAAAAAYY to.

Poh TAAAAAHHHH to.

Boil 'em, mash 'em, stick 'em in a stew!
 
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