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Arcanyn
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11 Feb 2013, 1:10 am

Woodpecker wrote:
What about a proton conductor where the main charge carrier is the proton, also what about a beam of positrons ? Strictly speaking a beam of electrons or protons from a cyclotron is an electric current.


Or in the case of electrolysis, current simultaneously flows in both directions. For instance, when electrolysing sodium chloride, the positively charged sodium ions will travel to the negative end whilst the negatively charged chloride ions migrate to the positive end.



jdbob
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11 Feb 2013, 1:48 am

Nambo wrote:
So Iam watching a film that states that electrons will always try to get from a negatively charged body, to one that is positively charged.
So why therefore, does a diode pass electricity freely from positive to negative?


Positive will flow from the anode to the negative cathode. Likewise negative will flow from the cathode to the positive anode. You can look at it either way. I've always found it easier to think of it as the first case. You get into the same situation with PNP versus NPN or PFET versus NFET.



LupaLuna
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11 Feb 2013, 2:07 am

Nambo wrote:
So Iam watching a film that states that electrons will always try to get from a negatively charged body, to one that is positively charged.
So why therefore, does a diode pass electricity freely from positive to negative?


A lot of people get the diode direction confused because of how the schematic symbol is written. if you look at the schematic symbol for the diode. The anode triangle get confused with being an arrow pointing from positive to negative thus confusing some people into believing that electricity flow from positive to negative.



Apple_in_my_Eye
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11 Feb 2013, 4:39 am

Woodpecker wrote:
What about a proton conductor where the main charge carrier is the proton, also what about a beam of positrons ? Strictly speaking a beam of electrons or protons from a cyclotron is an electric current.

I read something in New Scientist where someone accidentally found a substance that can switch a current of H+ ions/protons like a transistor.

Quote:
Scientists at University of Washington have built a novel transistor that uses protons, opening the door to a new class of bio-compatible solid-state devices that can potentially communicate directly with living things.

http://www.zdnet.com/blog/emergingtech/ ... hings/2849



ruveyn
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12 Feb 2013, 11:34 am

jdbob wrote:
Nambo wrote:
So Iam watching a film that states that electrons will always try to get from a negatively charged body, to one that is positively charged.
So why therefore, does a diode pass electricity freely from positive to negative?


Positive will flow from the anode to the negative cathode. Likewise negative will flow from the cathode to the positive anode. You can look at it either way. I've always found it easier to think of it as the first case. You get into the same situation with PNP versus NPN or PFET versus NFET.


Electrons are more moveable than protons. The protons are in the nuclei of metals and minerals more or less bound together as crystals or quasi-crystals. Electron are easy to bump off of the outer shells by photons. So it is the electrons that move.

ruveyn



jdbob
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13 Feb 2013, 1:50 am

ruveyn wrote:
Electrons are more moveable than protons. The protons are in the nuclei of metals and minerals more or less bound together as crystals or quasi-crystals. Electron are easy to bump off of the outer shells by photons. So it is the electrons that move.


My point is that unless you are designing semiconductors it really doesn't matter, it's just a matter of perspective.



ruveyn
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13 Feb 2013, 11:29 am

jdbob wrote:
ruveyn wrote:
Electrons are more moveable than protons. The protons are in the nuclei of metals and minerals more or less bound together as crystals or quasi-crystals. Electron are easy to bump off of the outer shells by photons. So it is the electrons that move.


My point is that unless you are designing semiconductors it really doesn't matter, it's just a matter of perspective.


You have a point. When an electron moves from Here to There a Hole moves from There to Here.

ruveyn