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| "Veritasium" (YT) - "The Big Misconception About Electricity" ? |
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| Berni:
--- Quote from: aetherist on May 10, 2022, 07:16:31 am ---A measure of the delay for the reflexion of a signal or pulse or something for a straight (single) bit of insulated Cu would do the job (say 10 m long if a good scope). Not coax. Not twin. Not ladderline. I say the speed of electricity will be 5.0 ns/m, which is 2c/3. A bare wire would be 3.4 ns/m, which is c/1. This is the speed of the fastest signal (which will probly be very strong with a steep rise, if the scope is a good scope). But i haven't got a scope. --- End quote --- If you have a straight conductor with nothing else around it you have created an antenna. The speed in these is well known to be close to the speed of light since this is important in antenna design. They are designed according to the wavelength and as you see using insulated wire makes a difference of only a few %, certainly not 2/3c. And it makes sense sine most of the surrounding environment is air with a tiny bit of plastic in it. There is also the problem with monopole antennas that you can't make a true monopole antenna. Current always flows in loops so driving this kind of antenna also pushes an identical reverse current into the ground. So whatever is connected to ground becomes 'the other piece of wire'. In real antennas this ground tends to be connected to a metal grounding rod right next to it to make the planet itself the other pole of the 'monopole' So to actually do your experiment properly one would need to do it using a 10m metal rod flying in the air with the measurement setup stuck to one end of it. That way you would have nothing conductive anywhere near the antenna (inducing the ground) while the test electronics are powered by batteries. What you would get in that case is mostly the ground of your test equipment getting wiggled up and down at the square wave pulse rate. The metal case of the equipment acting mostly as the antenna while using the 10m pole as its earth. |
| penfold:
--- Quote from: adx on May 10, 2022, 08:29:00 am --- --- Quote from: aetherist on May 09, 2022, 11:35:53 pm ---What is your own explanation for the rise & plateau? --- End quote --- Probing (is my guess). --- End quote --- Yeah... this ain't exactly paradigm-shifting experimentation, with absolutely no discredit to Derek at all, the experiment is only really set up to answer the question "does energy arrive at the load before anything traveling at the speed of light could travel the distance of the wires?": whilst it'd be nice to see something that truly matched (simplified) theory and simulation... it'd take a substantial amount of effort to simulate all physical artifacts or eradicate anything not simulated. So, I don't blame him, but recirculating my original stance, it's quite improper to draw any other conclusion without further investigation from such an experiment. Anyway, interesting point you (adx) made previously about the hydraulic analogy... I did wonder, much earlier on, whether Derek was simply setting us up for a video entitled "The big misconception about hydraulics". Extending the "rubber hoses in air" (the hoses being somewhat compliant and able to transmit a pressure wave), I wondered what would happen if the hydraulic circuit were constructed, rather than with tube in air, with cavities, channels, or tunnels within a soft and gelatinous medium (low-durometer silicone rubber perhaps). From the pressure of fluid within a cavity, the resulting dimensional change of that cavity could transmit a wave throughout the medium and affect the displacement of fluid elsewhere in the "circuit"... interestingly, because we have some control of the material properties, we can have a medium that only conveys the wave resulting from pressure and surely could only transmit power in a transient/continuously varying sense. We could at least hypothesize a fluid that is inelastic but moderately viscous (and immiscible with the hydraulic fluid) and can move slightly under the influence of friction with that moving fluid - where we could have a wave of movement. I've not really thought about it beyond that point, but it is easy to see where the aether concept arose. |
| aetherist:
--- Quote from: Berni on May 10, 2022, 09:26:25 am --- --- Quote from: aetherist on May 10, 2022, 07:16:31 am ---A measure of the delay for the reflexion of a signal or pulse or something for a straight (single) bit of insulated Cu would do the job (say 10 m long if a good scope). Not coax. Not twin. Not ladderline. I say the speed of electricity will be 5.0 ns/m, which is 2c/3. A bare wire would be 3.4 ns/m, which is c/1. This is the speed of the fastest signal (which will probly be very strong with a steep rise, if the scope is a good scope). But i haven't got a scope. --- End quote --- If you have a straight conductor with nothing else around it you have created an antenna. The speed in these is well known to be close to the speed of light since this is important in antenna design. They are designed according to the wavelength and as you see using insulated wire makes a difference of only a few %, certainly not 2/3c. And it makes sense sine most of the surrounding environment is air with a tiny bit of plastic in it. There is also the problem with monopole antennas that you can't make a true monopole antenna. Current always flows in loops so driving this kind of antenna also pushes an identical reverse current into the ground. So whatever is connected to ground becomes 'the other piece of wire'. In real antennas this ground tends to be connected to a metal grounding rod right next to it to make the planet itself the other pole of the 'monopole' So to actually do your experiment properly one would need to do it using a 10m metal rod flying in the air with the measurement setup stuck to one end of it. That way you would have nothing conductive anywhere near the antenna (inducing the ground) while the test electronics are powered by batteries. What you would get in that case is mostly the ground of your test equipment getting wiggled up and down at the square wave pulse rate. The metal case of the equipment acting mostly as the antenna while using the 10m pole as its earth. --- End quote --- The say 10 m wire could be stretched high above the dirt, from the say 3rd floor of a building, using plastic rope going to the say adjacent building. But i would not worry too much. Minor reflexions etc shouldn’t matter much, as long as there is a clear strong non-ambiguous signal. I would connect the wire to the scope (ie to receive a pulse), & not worry about completing some kind of circuit (or about using ground)(but i scored i think 51/100 for Electricity-1). I suppose that u would need the scope to measure voltage across a resistor stuck on the near end of the wire. Rather than using a (simple) pulse, i would prefer to use a (complicated) 12 V lead acid battery. Feed the wire from the negative terminal. Don’t have any connection to the positive terminal. Possibly use a special switch. No great need to looz sleep about all of the things needed to make the experiment perfect. The Nobel Committee will have an easy job. |
| Berni:
--- Quote from: aetherist on May 10, 2022, 10:57:46 am ---The say 10 m wire could be stretched high above the dirt, from the say 3rd floor of a building, using plastic rope going to the say adjacent building. But i would not worry too much. Minor reflexions etc shouldn’t matter much, as long as there is a clear strong non-ambiguous signal. I would connect the wire to the scope (ie to receive a pulse), & not worry about completing some kind of circuit (or about using ground)(but i scored i think 51/100 for Electricity-1). I suppose that u would need the scope to measure voltage across a resistor stuck on the near end of the wire. Rather than using a (simple) pulse, i would prefer to use a (complicated) 12 V lead acid battery. Feed the wire from the negative terminal. Don’t have any connection to the positive terminal. Possibly use a special switch. No great need to looz sleep about all of the things needed to make the experiment perfect. The Nobel Committee will have an easy job. --- End quote --- A scope measures all signals in reference to ground, so you have to connect ground somewhere. The signal generator making the pulse (or a battery and switch) also has two terminals, so you need to connect the other end to something to see a signal at all. The source can only 'pump' electrons over. So if you want to push electrons into the 10m rod you have to pump them from somewhere. |
| SandyCox:
--- Quote ---The Nobel Committee will have an easy job. --- End quote --- For once I agree with you! |
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