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Electroboom: How Right IS Veritasium?! Don't Electrons Push Each Other??
electrodacus:
--- Quote from: gnuarm on July 21, 2022, 06:20:10 am ---This video shows the car working exactly as I described it. In the beginning, you are doing something that makes the car move with the paper without the wheels turning. But once you reposition the car, it moves opposite to the motion of the paper (the treadmill) which is exactly what I said it would do.
How can you be in denial of your own evidence??? The fact that your wheels are not very sticky and slip a lot, doesn't mean it's not working. The slipping is what screws it up. When the wheels don't slip, the car moves opposite the paper. The wheels are turning and not slipping, proving your idea of the wheels being "gearbox locked" is pure bunkum.
--- End quote ---
In the beginning the back wheels are on top of some solder wire 0.8mm diameter so that they have less contact surface (still fairly good as it is rubber wheels on metal) but worse than front wheels that are rubber on paper.
The video is specifically designed to show that is you remove the ability of front wheels to slip (the ones on the moving paper) the vehicle is just locked and it is dragred in the direction the paper moves as it is a locked gearbox by design.
The second half of the video shows what happens when front wheels (those on moving paper) are allowed to slip and that was also shown in slow motion video where you can better see how it works with belt being stretched (energy stored) then when wheels slip stored energy is discharged allowing a bit of motion against the direction of the treadmill then cycle repeats.
Any vehicle designed this way even with a chain will work the same way. You will just need a slow motion video to see the details.
You just do not get that any force F1 applied will result in F2 being equal and opposite direction. That is because you are not used with a vehicle being pushed from outside in that way. The vehicle will want to move in the direction is being pushed except the way the belt is connected it can't as it is locked so it will either slip in the direction is pushed (first part of the video) or energy is stored and then generator wheel slips allowing the motor wheel using the stored energy to move a bit forward then wheel locks again and cycle repeats (normally this is faster than you can see in a normal speed video).
gnuarm:
--- Quote from: electrodacus on July 21, 2022, 06:51:03 am ---
--- Quote from: gnuarm on July 21, 2022, 06:20:10 am ---This video shows the car working exactly as I described it. In the beginning, you are doing something that makes the car move with the paper without the wheels turning. But once you reposition the car, it moves opposite to the motion of the paper (the treadmill) which is exactly what I said it would do.
How can you be in denial of your own evidence??? The fact that your wheels are not very sticky and slip a lot, doesn't mean it's not working. The slipping is what screws it up. When the wheels don't slip, the car moves opposite the paper. The wheels are turning and not slipping, proving your idea of the wheels being "gearbox locked" is pure bunkum.
--- End quote ---
In the beginning the back wheels are on top of some solder wire 0.8mm diameter so that they have less contact surface (still fairly good as it is rubber wheels on metal) but worse than front wheels that are rubber on paper.
The video is specifically designed to show that is you remove the ability of front wheels to slip (the ones on the moving paper) the vehicle is just locked and it is dragred in the direction the paper moves as it is a locked gearbox by design.
The second half of the video shows what happens when front wheels (those on moving paper) are allowed to slip and that was also shown in slow motion video where you can better see how it works with belt being stretched (energy stored) then when wheels slip stored energy is discharged allowing a bit of motion against the direction of the treadmill then cycle repeats.
Any vehicle designed this way even with a chain will work the same way. You will just need a slow motion video to see the details.
You just do not get that any force F1 applied will result in F2 being equal and opposite direction.
--- End quote ---
It's not a matter of not "getting it". I am saying you are dead wrong about that. There is zero reason to think that is correct.
At the 20 second mark, the car gets some traction with the paper and the other surface, and does exactly what I predicted, moving opposite the direction of the paper (treadmill).
--- Quote ---That is because you are not used with a vehicle being pushed from outside in that way. The vehicle will want to move in the direction is being pushed except the way the belt is connected it can't as it is locked so it will either slip in the direction is pushed (first part of the video) or energy is stored and then generator wheel slips allowing the motor wheel using the stored energy to move a bit forward then wheel locks again and cycle repeats (normally this is faster than you can see in a normal speed video).
--- End quote ---
You have no clue. You make up all manner of silly stuff.
Make a video where you pick up the car and turn the wheels by hand. That will show they are not "locked". Put marks on the wheels, so we can count the turns. You can turn one wheel some number of turns, and we can count the number of turns on the other wheel. THAT is a constant. Unless you use crappy surfaces where the wheels slip, that ratio determines where the car goes.
You have no clue about any of this. Literally no clue. I'm pretty sure you do not have a technical job. It's not possible.
Nominal Animal:
--- Quote from: dunkemhigh on July 20, 2022, 09:38:37 pm ---
--- Quote ---when the circuit is first closed, regardless of the current being AC or DC.
--- End quote ---
For a very brief moment, it's AC even when it's DC, isn't it?
--- End quote ---
Yes, exactly. The faster the rise, the higher frequency components you have in it.
Just like when doing logic circuits, you get all sorts of AC effects from the pulses, which need to be dealt with in real life circuits.
--- Quote from: Naej on July 20, 2022, 11:12:46 pm ---
--- Quote from: Nominal Animal on July 20, 2022, 09:09:27 pm ---"Will move". No, something makes them move. That something is an electric field, which propagates through the circuit somewhat analogously to a shock wave when the circuit is first connected. Also, some of the original "potential energy" is in the form of an electric field around the charged plate; it is not exactly correct to just lump it all into "potential energy" and call it good enough.
--- End quote ---
Or maybe it is correct.
--- End quote ---
Not exactly correct means it is an approximation.
When you are arguing about exactly where the majority of the energy flow in a system is, making such approximations is exactly how you "accidentally" manipulate it to fit your pre-selected model.
Consider this question: Are the participants arguing where the energy flows, or what the setup being investigated exactly is?
To me, the disagreement stems from the latter, and is the reason why I'm not interested in their arguments and opinions, be they professors or internet celebrities or whatever else. I am too familiar with both "garbage data + good model = garbage results" and "good data + garbage model = gargabe results" already; I want to drop the garbage parts and have people spend their time on the "good data + good model = good results" case instead.
In this case, each participant has their own model. That's no good: OF COURSE their inner workings vary then, even if the results are exactly the same.
m k:
--- Quote from: Nominal Animal on July 20, 2022, 09:09:27 pm ---
--- Quote from: electrodacus on July 20, 2022, 06:44:51 pm ---You are confusing some things.
--- End quote ---
No, you're leaving important bits out, oversimplifying the situation to fit your axiomatic model.
--- Quote from: electrodacus on July 20, 2022, 06:44:51 pm ---As soon as you close the switch the excess electrons from one plate will move in to wire which is neutrally charged and at the same time on the other plate electrons from the wire will migrate in to the plate with deficit of electrons.
--- End quote ---
"Will move". No, something makes them move. That something is an electric field, which propagates through the circuit somewhat analogously to a shock wave when the circuit is first connected. Also, some of the original "potential energy" is in the form of an electric field around the charged plate; it is not exactly correct to just lump it all into "potential energy" and call it good enough.
When the circuit has stabilized, the electric field (potential difference along the circuit) has subsided to something small and stable, aside from thermal noise and such. This does not mean it was small and stable and insignificant at the violent beginning.
--- Quote from: electrodacus on July 20, 2022, 06:44:51 pm ---While electron wave travels through wire
--- End quote ---
What electron wave? You need to specify that too, and not just give it a name and leave it at that. Giving a thing a name is not the same as describing the thing.
Each individual electron is both a particle and a wave. When an electron is bound to an atom, it is delocalized in the shape described by spherical harmonics. When an electron is shared by a lattice (as they are in metal conductors), they are delocalized in various ways, and typically spread over or "shared" across multiple lattice atoms.
If we describe electron locations by the center or centroid of their delocalized volume, they really do move very slowly, something like a meter a second or so, often even slower, while the current and changes in the current propagate at over half the speed of light, or over hundred million times faster.
The electrons do not just push each other to move (as described in electrostatic approximation as the Coulomb force); they also interact via emitting and absorbing photons, and coupling to existing electromagnetic fields like the one caused by being matter not cooled to absolute zero. Note that this EM field is NOT just "radiating outwards"; there is always both emission and absorption.
So, what you call "electron wave" is in reality a set of various possible interactions. The majority (i.e., which kind of interaction is the most common or involves the most energy flow) depends on the exact configuration of the system; its geometry.
It is somewhat funny that the most complex phenomena occur when the circuit is first closed, regardless of the current being AC or DC. This case has always wavelike properties, and being non-equilibrium situation, you have all kinds of energy flows all over. Even if we assume a perfect switch, something that changes from 0 to 1 without any intermediate states in between, it still is a step-like pulse with a lot of higher frequency components, and thus definitely a wave. Ramping the current smoothly has a nicer spectrum, but a time-discontinuous signal always contain lots of frequencies.
While the transmission line model does describe the observable voltages and currents at the ends of the line when the properties of the transmission line are known, it does not mean it is a complete picture of the interactions involved. The fact that the model is based on electromagnetic waves, should make it obvious that it is not just about electron kinematics, but electromagnetic field interactions must play a significant role, too.
To explore the complete picture in a way consistent with our best understanding of physics, one needs to delve into quantum electrodynamics, which definitely belongs to the less intuitive section of physics. I definitely have no idea how to even start describing it in laymans terms.
--- End quote ---
At the beginning QED is pretty simple, just follow the experiment and digest.
If you diminish your light source enough your light indicator starts blinking.
If you then put another light indicator beside the first one they both blink but not simultaneously.
If you then put many light indicators side by side they all blink but only one at the time and eventually they've all blinked equal amounts.
We've given that quantized random light a name photon.
Things become even more interesting if you put few slits between that light source and its indicators.
You can make the apparatus from a quality laser pointer, a comb and plain paper.
Block all but two adjacent comb spike intervals and point the laser to the wall through the comb.
Distances are not relevant, only clearness of the result will change.
You can also make the apparatus from a plain paper.
Make a diminishing monocular, construction must be light tight so that model type can be easier.
Punch a pin hole to the input, two close by holes to output and one hole to the middle.
Single holes must be so small that finally only coherent light goes through.
Double holes can be bigger but bigger ones need more light for better contrast.
Then just point a light to the wall through the decoration.
If the thing works you should see a string of bars or spots coming out from two slits or holes.
For explaining that all we need probability waves.
It's now a hundred years old discovery so many generations of scientists are educated and for some the probability part is dropped out.
So for them the wave is pretty real even that they argue that real can be measured.
The phenomena itself is very real of course, our computerized world is based on it.
Good thing to remember if you start arguing over the net.
electrodacus:
--- Quote from: gnuarm on July 21, 2022, 06:57:29 am ---It's not a matter of not "getting it". I am saying you are dead wrong about that. There is zero reason to think that is correct.
--- End quote ---
Let's look at the extreme case.
a) Wheels are not connected and free to rotate zero friction. The vehicle will just stay in place while the wheel on treadmill will rotate.
b) Wheels are welded to vehicle frame. The vehicle will either stay in place if the wheel on treadmill slips or it will move from right to left if wheel on red box slips.
c) Wheels are connected with a twisted belt (think at infinity symbol shape ∞) and pulley have the same diameter 1:1 gear ratio. The vehicle will move easily from right to left so in the direction the treadmill moves.
d) Wheels are connected as in my diagram but pulley are equal gear ratio 1:1. The vehicle will wheels will be locked no different than point b) so one of vehicle wheels will need to slip.
Hopefully you can agree with all 4 points.
If you do then the only thing you need to understand is that when gear ratio is say 2:1 the force F2 can not be larger than F1 not until wheel on treadmill slips.
Newton's 3'rd law applies in this particular case due to the place and direction that F1 is applied to vehicle.
Maybe imagine treadmill moving in the other direction all things being equal as in my diagram. The gearbox will still be locked and one of the wheels will still need to slip.
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