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| "Veritasium" (YT) - "The Big Misconception About Electricity" ? |
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| aetherist:
--- Quote from: SandyCox on February 12, 2022, 12:42:29 pm --- --- Quote from: aetherist on February 12, 2022, 11:08:22 am --- --- Quote from: SandyCox on February 12, 2022, 10:51:47 am ---https://archive.org/details/ThePhysicsOfVibrationsAndWavesH.J.Pain/page/n15/mode/2up --- End quote --- That looks to be a dy/dt transverse particle velocity, not a dx/dt. --- End quote --- Exactly! The particle and wave velocities are not equal. " The particle velocity ... is therefore given as the product of the wave velocity...and the gradient of the wave profile preceded by a negative sign for a right-going wave..." I suggest that you read the whole chapter. Its quite an eye opener. --- End quote --- Yes, a slow transverse wave can in a say stiff bar propagate longitudinally very fast. It might be possible to invoke that kind of relationship for em radiation for electricity along a wire. Probably can't be done. A generator would have to give electrons a transverse say up'n'down motion. Or perhaps a generator would have to give electrons a spin or a precession or nutation whereby the electron could be static or in a slow uniform motion but the precession etc might propagate at the speed of light. Interesting. |
| SandyCox:
--- Quote from: aetherist on February 13, 2022, 07:47:30 am --- --- Quote from: SandyCox on February 12, 2022, 12:42:29 pm --- --- Quote from: aetherist on February 12, 2022, 11:08:22 am --- --- Quote from: SandyCox on February 12, 2022, 10:51:47 am ---https://archive.org/details/ThePhysicsOfVibrationsAndWavesH.J.Pain/page/n15/mode/2up --- End quote --- That looks to be a dy/dt transverse particle velocity, not a dx/dt. --- End quote --- Exactly! The particle and wave velocities are not equal. " The particle velocity ... is therefore given as the product of the wave velocity...and the gradient of the wave profile preceded by a negative sign for a right-going wave..." I suggest that you read the whole chapter. Its quite an eye opener. --- End quote --- Yes, a slow transverse wave can in a say stiff bar propagate longitudinally very fast. It might be possible to invoke that kind of relationship for em radiation for electricity along a wire. Probably can't be done. A generator would have to give electrons a transverse say up'n'down motion. Or perhaps a generator would have to give electrons a spin or a precession or nutation whereby the electron could be static or in a slow uniform motion but the precession etc might propagate at the speed of light. Interesting. --- End quote --- I suggest that you also read the next chapter on longitudinal waves. The speed at which an electromagnetic wave propagates is not the same as the electron drift speed. The wave can propagate without the presence of electrons. That's how sunlight reaches the earth. |
| aetherist:
--- Quote from: SandyCox on February 13, 2022, 08:12:45 am --- --- Quote from: aetherist on February 13, 2022, 07:47:30 am --- --- Quote from: SandyCox on February 12, 2022, 12:42:29 pm --- --- Quote from: aetherist on February 12, 2022, 11:08:22 am --- --- Quote from: SandyCox on February 12, 2022, 10:51:47 am ---https://archive.org/details/ThePhysicsOfVibrationsAndWavesH.J.Pain/page/n15/mode/2up --- End quote --- That looks to be a dy/dt transverse particle velocity, not a dx/dt. --- End quote --- Exactly! The particle and wave velocities are not equal. " The particle velocity ... is therefore given as the product of the wave velocity...and the gradient of the wave profile preceded by a negative sign for a right-going wave..." I suggest that you read the whole chapter. Its quite an eye opener. --- End quote --- Yes, a slow transverse wave can in a say stiff bar propagate longitudinally very fast. It might be possible to invoke that kind of relationship for em radiation for electricity along a wire. Probably can't be done. A generator would have to give electrons a transverse say up'n'down motion. Or perhaps a generator would have to give electrons a spin or a precession or nutation whereby the electron could be static or in a slow uniform motion but the precession etc might propagate at the speed of light. Interesting. --- End quote --- I suggest that you also read the next chapter on longitudinal waves. The speed at which an electromagnetic wave propagates is not the same as the electron drift speed. The wave can propagate without the presence of electrons. That's how sunlight reaches the earth. --- End quote --- Photons (eg sunlight) are not an em rolling wave. Nothing is. There is no rolling. E×H is always a fixed slab. Hertz was wrong. Maxwell might have been wrong too (i don’t remember what he said exactly). 1. Old electricity has it that drifting electrons produce an electric wave that propagates at almost c/1. I think that a mechanical Newtonian analysis (for electrons bumping electrons) would show a wave speed less than c/100,000,000. 2. Electrons have mass, ie inertia, hence high speed (see (3)) would need a lot of energy. 3. A simple longitudinal wave (electrons bumping electrons) requires that the particles producing the simple wave each move at at least the speed of the wave, at least briefly, for at least a small distance (see (2)). 4. The speed of em radiation in Cu is 3.2 m/s for AC of 60 Hertz (says wiki). I have been saying that the speed is about 10 m/s for DC. 3.2 m/s is nearnuff c/100,000,000. Electrons bump electrons via their em radiation, hence how can a wave propagate faster than their (bumping) radiation? 5. A drift speed of 0.0001 m/s is c/300,000,000,000. However i recognise that a slow drift speed does not rule out the possibility of a very very fast wave. 6. Free-ish conduction electrons will already have lots of speed (due to temperature etc) even when their drift speed is zero m/s. Hence drift speed requires additional energy. U know what i mean. 7. The drift path of free-ish conduction electrons will not be directly along a wire, a tortuous 3D internal path might double the path distance along a wire, if so then the electron-to-electron bumping wave would need to propagate at 2c/1 along the tortuous long route if it is to give c/1 along the direct route. 8. Drifting electrons it is said suffer a resistance to their drift, resulting in electrical resistance, resulting in heat. Any such loss/resistance will affect the speed of the wave. 9. And we can add that old electricity has no good explanation re how painting some enamel on a bare wire slows the electricity from c/1 for the bare wire down to 2c/3 for the enamelled wire. 10. And after someone shows that producing a screw thread on the surface of a wire slows the electricity then old electricity will have no good explanation for that either. 11. Re (10), i suggest that Dave do the X before Derek or Brian or Mehdi does it. Howardlong with his 20 GHz scope could do it with a 12" threaded rod. |
| eugene:
Consider this: we take a pipe and stuff it full of marbles so that there is no room for any more. Now stuff another marble in one end. What happens? Obviously an identical marble pops out the other end. How long was the delay between when the first marble was stuffed in and the other one popped out? Don't need an exact number; was it fast or slow? If you continuously stuff marbles in one end, what's the drift velocity of the marbles? How does this compare to the speed that the information got from one end of the pipe to the other? |
| aetherist:
--- Quote from: adx on February 13, 2022, 03:36:57 am --- --- Quote from: aetherist on February 12, 2022, 09:26:29 pm ---I hope that readers here are starting to see how my new electricity ticks all of the boxes. --- End quote --- Yes, the G-string result has parallels with your theory (which is why I posted it). I see some inconsistency in your descriptions. If an electon has difficulty clinging to an extremely mild curve in a G-line, then what makes some happily navigate a sharp 90 deg bend? "if it duznt detach" isn't an answer, it is a question. --- End quote --- A 180 deg u-turn around a wire of radius R (ie at a sharp bend in the wire) would be more drastic for an electon than a 90 deg turn along a radius of R (ie to follow the surface of a 90 deg sharp bend in a wire)(depending on the exact 3D geometry of the u-turn or bend). Actually i reckon that microscopic grooves & scratches etc would be critical. Painting enamel on the wire to slow the electons to 2c/3 (to reduce the % escaping at bends) seems to be logical. But i reckon that they should have used fatter wire, to reduce the crowding of the electons, ie to reduce the repulsions that give a concentration of (negatively charged) electons on the outside of their (slight) bends. Perhaps they explain why they use thin wires. It might be so that they can more easily tighten the wire to reduce their (slight) bends. --- Quote from: adx on February 13, 2022, 03:36:57 am ---Also you posited that electons are photons which travel (primarily?) on the outside of conductors, because EM travels at ~10m/s in copper if I got that right. In which case, your "reflexion" description describes surface electons either progressing around the corner or radiating away, but inner electons always reflect (at 10m/s). --- End quote --- Electons hug the outside of a wire, whilst propagating at the speed of light. But electons can hug the surfaces of voids inside a wire if the wire is porous (if the electon has somehow managed to enter the wire, ie from its natural location on the outside surface of the wire). In which case for sure the internal electon might be slowed by whatever it is that slows em radiation, especially if the void is very narrow. Electons might be able to reflect in certain situations, ie like an ordinary free photon. But i reckon that electons don’t reflect at bends in a wire or at loads (resistances) in a wire, electons do u-turns, or what i mean is that the surface does a u-turn (electons go straight ahead as usual). When i say straight ahead i need to add that electons being negatively charged can be guided somewhat by outside influences (by electric fields). And i suppose by magnetic fields, i havnt thought about that (i will have to have a think). If em radiation is called electromagnetic radiation then perhaps i should call electric fields electro fields. Yes, i might do that from now on. --- Quote from: adx on February 13, 2022, 03:36:57 am ---How do you explain a reflection of spacetime ("its the surface that has done the u-turn") if you deny 'Einsteinian' time contraction? --- End quote --- All of Einstein's Relativity is rubbish. His spacetime is rubbish (actually i don’t think that he believed in spacetime either). But i don’t see how Einsteinian time dilation rears its ugly head in old electricity. Or in reflexion. --- Quote from: adx on February 13, 2022, 03:36:57 am ---Maybe your theory does tick all of the boxes (I'm not implying I think it does), but what it is also doing is adding mystery, like why electons roam around on the surfaces of battery plates while sitting in the shop, not slowly, but at the speed of light. That is an awful lot of activity for something which appears for all intents and purposes to be static, again the question is not whether they do (in the theory they do), but why they should want to - a good reason for being, beyond being an option which seems to make sense to some people in certain settings (our complaint over the Poynting vector). --- End quote --- Electons are photons. All photons propagate at the speed of light. They can do no other. Electons roam the surface of the negative battery terminal, in effect for ever, they don’t suffer any energy loss (i think). --- Quote from: adx on February 13, 2022, 03:36:57 am ---What this ticked box adds to human 'knowledge' is a question. Each postulate also exists without quantified links to reality (measurement). By that I mean the numerical behaviour which explains (accurately) things like how many electons peel off the wire under defined circumstances. In time this would achieve predictive power beyond being a rough mental crutch to help think through physics situations. In spite of all this box ticking, the mystery quotient is increasing in an unbounded way. --- End quote --- I don’t think that we have any good info re when electons peel off a G-string wire & when they don’t. If u want a prediction, then how about my prediction that electricity goes slower when a wire has a screw thread on its surface. This is explained by electons having to propagate further up'n'down over the threads. If u want a numerical postdiction, then how about when a capacitor is discharged the discharge has half of the theoretical voltage for twice the theoretical time. This is explained by my electons roaming all of the surfaces. Electons going away (ie a half of all of the electons) have to do a u-turn to come back. Hence half the voltage for twice the time. What better proof (or at least confirmation) for my electons would anyone want. --- Quote from: adx on February 13, 2022, 03:36:57 am ---For all its deep mystery (which equates to perhaps an inability to tick a box), conventional electricity theory does make good 'reasons for being' for nearly everything (electrons drift because of electric field and carry potential energy around, skin effect results from inductance and resistance). It also ties all this behaviour together with extremely robust predictive capability which works to "umpteen decimals" (much more accurate than you seem to think), being formulated in terms of mathematics more than thoughts. In that respect its inventors went for the jugular, being all hopped up on science, as was the fashion of the day. It perhaps lacked some imagination. To that end, continuing on from my earlier post about Popper falsifiability, a good ideal to shoot for might be for half your ideas to fail: Much less, could mean you are either being too unimaginative, or testing too little (or combination). --- End quote --- Old electricity fails in so many ways. I already mentioned that it is 100% out for predicting the discharge voltage of a capacitor. I already mentioned that it is 100% out for predicting the discharge time for a capacitor. I already mentioned that it is 50% out for predicting the speed of electricity along an enamelled wire. But i don’t agree re ideas failing, i reckon that every box has to be ticked, one strike & new electricity is out. But perhaps it would not be out. After all, old electricity (electron drift) has been around since electrons were discovered or invented in 1897, & it fails to tick many boxes, but has been handy anyhow. So, if new electricity fails to tick a box then we could still use it or parts of it until something better comes along. Thats the way it has always been & ever will be. |
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