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| This electons flowing rubbish |
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| JohnnyMalaria:
--- Quote from: ledtester on March 02, 2021, 05:43:43 pm ---Are you concerned that it's not the same electron that skips from atom to atom? Problem solved: https://en.wikipedia.org/wiki/One-electron_universe --- End quote --- I remember my high school physics teacher explaining this in 1981! |
| TimFox:
--- Quote from: JohnnyMalaria on March 02, 2021, 12:17:45 am ---Um, what about situations where the movement of electrons (or other charged particles) generates the voltage??? --- End quote --- The only examples I can think of where the electron current generates a voltage (as opposed to being the result of an applied voltage) are: 1. Photovoltaic cells, under illumination. 2. A vacuum diode (or other tube) with a hot cathode and a resistor from the anode (or grid for a triode) back to the cathode, where the energetic electrons thermally emitted from the cathode induce a current in the (usually high-value) resistor. Beta emission from a radioactive source would be similar. In the case of induction from a changing magnetic field, the changing flux linking the circuit induces an EMF around the circuit, which then causes current to flow through the conductors and other elements of the closed circuit. |
| JohnnyMalaria:
--- Quote from: TimFox on March 02, 2021, 09:43:27 pm --- --- Quote from: JohnnyMalaria on March 02, 2021, 12:17:45 am ---Um, what about situations where the movement of electrons (or other charged particles) generates the voltage??? --- End quote --- The only examples I can think of where the electron current generates a voltage (as opposed to being the result of an applied voltage) are: 1. Photovoltaic cells, under illumination. 2. A vacuum diode (or other tube) with a hot cathode and a resistor from the anode (or grid for a triode) back to the cathode, where the energetic electrons thermally emitted from the cathode induce a current in the (usually high-value) resistor. Beta emission from a radioactive source would be similar. In the case of induction from a changing magnetic field, the changing flux linking the circuit induces an EMF around the circuit, which then causes current to flow through the conductors and other elements of the closed circuit. --- End quote --- The solar wind is a good example. Also streaming potential and sedimentation potential (ions rather than electrons per se but the same idea). |
| jh15:
Long distance runner without a jock. |
| GlennSprigg:
--- Quote from: Terry Bites on March 01, 2021, 02:24:14 pm ---Why do people just keep on promoting bad science? Electrons do not flow in conductors or semiconductors or anything else when a current is flowing. Yeah Yeah drift current... diffusion current... blah. Charge is transported around the current path under the influence of the applied voltage. Let's stamp out the BS in EE! --- End quote --- I'm sorry my friend, but I can't even grasp what/(why) you are trying to say, there ??? ??? I think you might be intermixing & confusing yourself with a few basic electrical facts.... Firstly, of COURSE electrons actually physically flow in conductors, but maybe not in the way 'you' imagine it. Let's first clear up thoughts of the "Speed of Light". The ONLY thing that travels at the speed of light, is LIGHT. (And it does that at slightly varying speeds, whether through vacuum/air/diamond etc.! ). This actually has nothing to do with the apparent 'speed' of Electricity, which is simply the result of a 'knock-on' effect within the conductor. In say a 'Super-Conductor' situation, this knock-on effect is just a lot quicker! Now... My actual 'numbers' here are just to give you an idea, but even though, (talking about DC first!) when a difference of potential (voltage) is 'pushing' Electrons in one end of say a wire, and the apparent 'flow' is almost instantaneously apparent at the other end, the Electrons themselves did NOT actually travel that fast! :P Assuming that in a conductor, there is say 1-Amp flowing, then the ACTUAL physical 'Electrons' are only moving at (ABOUT!) say 1-Cm per Second!! And 'moving' in this way, they most certainly are !!! 8) However, for an AC circuit, (say 50/60 Hz), these 'same' electrons are just moving forwards & backwards again, in the same piece of wire! and never really getting anywhere... But 'moving' they most certainly are! :-+ |
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