For one, as soon as you start using the capacitor energy the voltage drops and then you'll start demanding a graph of voltage over time and wibbling on about how the energy is depleting and... well, you have form, let's put it like that.
For another the battey is going last a lot longer and give a steady output. That's all the reason the battery is there - it is a constant source. It's not ACTUALLY, a battery, but the circuit diagram doesn't have a symbol for a electrodacus-proof source, so that's the nearest we have.
And, no. There is negligible internal resistance in this source, so forget about diverting to a discussion of that.
Why do you think my equation will be valid for a sail powered vehicle driving directly down wind but not for one that has a propeller installed and connected to wheels ?
For one, as soon as you start using the capacitor energy the voltage drops and then you'll start demanding a graph of voltage over time and wibbling on about how the energy is depleting and... well, you have form, let's put it like that.
For another the battey is going last a lot longer and give a steady output. That's all the reason the battery is there - it is a constant source. It's not ACTUALLY, a battery, but the circuit diagram doesn't have a symbol for a electrodacus-proof source, so that's the nearest we have.
And, no. There is negligible internal resistance in this source, so forget about diverting to a discussion of that.
Voltage on any real battery will also drop and way less predictable.
In the SPICE simulation you do not define the length of the wire
I explained in the other thread, and amazingly that's when you took a sabbatical.
Essentially, if the prop is turning then it is pushing air. If that stream of air is going backwards then the velocity of the vehicle is the speed of the wind PLUS the speed of that backwards-streaming air.
Does your equation take account of that? Ergo it is not the right equation for this situation.
QuoteIn the SPICE simulation you do not define the length of the wire
You're a piece of work, eh. The wires are virtually non-existent. Zero length, as close as you can make them. Even if they were 10ft long (3m and a bit for the EU) whatever effect they could have would be NOTHING compared to the 1W burned up by the resistor, not the 1V of the supply.
It seems that you cannot actually answer the question and instead just go off on the slightest thing as a diversion.
But it does represent "the directional energy flux (the energy transfer per unit area per unit time)" to quote Wikipedia. So things like surface integrals can have a real physical interoperation.
And your quote proves that you don't even understand what that means.
It doesn't in any way show that electrical energy flows in one direction in a straight line instead of a loop. Or that Electricity flows outside of wires, or that waves and fields outside the wire are the primary source of energy rather than a secondary emission.
I could just as easily say that the electrostatic and magnetic field lines do not exist, just as isobars on the weather map don't exist either.
You couldn't say that about electrostatic and magnetic fields because they actually exist. There is no Poynting field. It's direction of pointing doesn't demonstrate that electricity flows outside of a wire in a straight line.
Differences in atmospheric pressure certainly exist and areas of equal pressure are directly represented by isobars.
If the local vector direction of the wind was combined with an isobar to create a third imaginary "aether" that moved in a different direction based on arbitrary rules then we would end up
with another imaginary concept that also doesn't exist.
Electric fields still exist when there is no movement of charged particles (electrostatic). But as you say, without magnetic fields the Poynting vector is zero.
But an electric field can't exist without an initial movement of charged particles in order to establish a potential difference. A surplus of electrons or a deficiency of electrons in electrical circuits.
My rejecting of power flowing in wires has very tittle to do with the Poynting Vector. Here is some of my various thoughts:
And that is why you decided to use the poynting vector to somehow prove that electricity flows outside of wires and travels in one direction in a monoline from source to load insinuating that you don't need a circuit loop lol.
1A flowing in a wire looks the same regardless if 1kW or 100mW of power is being transferred into the load. The only way to tell is to cut the wire, and measure the potential between the two end.
No it doesn't look exactly the same. One amp at a lower or higher voltage in the same circuit is going to inevitably show changes in potential difference at the load. You Don't need to cut the wire. You can measure the potential difference between two points in a continuous loop.
A raised negative potential indicates that there is a closer packing of flowing electrons for a given volume due to resistance limiting current flow. This creates an equal and opposite raised positive potential elsewhere due to a lower packing of flowing
electrons in a given volume.
If there was a significant electric field gradient within a wire, then any mobile charges in the wire would be accelerated. That would be doing work in the wire. The wire would tip over to having significant resistance, have a significant potential difference along it, and generate heat.
Electrons are electrostatically pushing each other in one direction through a conductor. They don't accelerate in DC ( but they do accelerate initially when the circuit is turned on ).
They are limited in movement by the electron in front, the electron behind and the positive charges of the atom nuclei. No acceleration in a wire if there is no alternating electromotive force.
In AC, electrons are constantly accelerating. If they didn't accelerate, antennas would never emit electromagnetic waves.
And Yes if the potential difference is great enough in DC, electrons can overcome the limiting forces of ordinary electron travel in a conductor/semiconductor or insulator and actually accelerate continuously in one direction only.
Other types of conducting mediums do not require special conditions for electrons to accelerate in DC.
In a cathode ray tube electrons are always accelerated. In a low pressure discharge lamp the electrons are always accelerated. In an electrical discharge (such as lightning), the electrons are always being accelerated.
Yes , all wires have resistance and a potential difference along them no matter how slight. The only exception being superconductors but even superconductors have a limit on the amount of current they can carry whilst remaining in a superconducting mode.
When current is flowing the charges are drifting along very slowly, and when no current is flowing the charges aren't moving at all - even if the wire is considered to be at a high potential! So whatever the conditions are that enabling an electron to do work are not present in a wire, (which I guess is what makes it a good wire).
If you switch on a circuit the first electron out the negative terminal pushes against the next electron via their negative electric fields. Because electrons have mass and thus momentum, it takes time for this electron to absorb the energy of the first electron and
then move forwards to push the next electron that will also take time to change direction due to momentum and attraction to the positive nuclei. Within a microscopic fraction of a second ( but well below the speed of light ) This cascading push of electrons will reach the opposite terminal and then all the electrons will be moving at a constant speed. The initial pulse of acceleration is gone because all the electrons are now moving in the same direction relative to the wire.
Yes, a high potential with a depletion or over abundance of electrons doesn't need any moving charge to MAINTAIN itself if it is free of leakage. (An electrical circuit is a continuous leakage of electrons from the cathode to the anode)
BUT, the only way to initially CREATE a high potential is by expending energy to forcefully move charged particles. In this case removing electrons from one side of a capacitor and placing them on the other side.
If you have a difference in potential between two plates and add a test charge between them it will experience a force. Whatever is providing the energy is present outside of the wires - the force has to be transferred some how.
This is unlike the water pressure is voltage in the "electricity is water" analogy, where you have to be in contact with the water make use of the energy. You can measure the pressure difference between two hoses, but if you put a glass of water between two hoses won't feel a force towards the hose with the lowest pressure.
No, you absolute @@@, The extra elections inside one plate of the capacitor are literally pulling on the electron depleted protons in the other plate... And you had to move electrons from one plate to the other in order to create a potential difference in the first place. The test charge also had to be created by expending energy to forcefully move electrons.
I think the underlying truth is "the conductors provide the charges, the fields supply the energy", and there are most likely deeper truths under that.
But for day-to-day electronics where stupidly high potentials and energies are not involved it makes no difference - the Lumped Element model works fine,
until your PCB designer forgets to put two inductors at right angles, or you get unexpected parasitic capacitance between traces, or some other reason that reality ruins your day.
Literally nothing you have ever said has demonstrated in any way that electricity actually flows outside a wire as waves or that fields outside a wire are the primary source of energy.
They aren't. The are a secondary effect of moving charged particles with mass inside a conductor.
In my opinion. The underlying truth is actually that low IQ adults and children love watching pop science crap on youtube produced by smoothbrains like Veritasium who's only talent is in
Getting millions of views and maximizing his own paycheck. He is a joke and you are also a joke if you think he cares or even thinks deeply about any of the concepts he talks about.
As another example, we ask what happens in a piece of resistance wire when it is carrying a current. Since the wire has resistance, there is an electric field along it, driving the current.
...
There is a flow of energy into the wire all around. It is, of course, equal to the energy being lost in the wire in the form of heat. So our “crazy” theory says that the electrons are getting their energy to generate heat because of the energy flowing into the wire from the field outside. Intuition would seem to tell us that the electrons get their energy from being pushed along the wire, so the energy should be flowing down (or up) along the wire. But the theory says that the electrons are really being pushed by an electric field, which has come from some charges very far away, and that the electrons get their energy for generating heat from these fields. The energy somehow flows from the distant charges into a wide area of space and then inward to the wire.
Now we take another example. Here is a rather curious one. We look at the energy flow in a capacitor that we are charging slowly. (We don’t want frequencies so high that the capacitor is beginning to look like a resonant cavity, but we don’t want dc either.) Suppose we use a circular parallel plate capacitor of our usual kind, as shown in Fig. 27–3. There is a nearly uniform electric field inside which is changing with time. At any instant the total electromagnetic energy inside is u times the volume.
... snip out the maths ...
So there must be a flow of energy into that volume from somewhere. Of course you know that it must come in on the charging wires—not at all! It can’t enter the space between the plates from that direction, because E is perpendicular to the plates; E×B must be parallel to the plates.
... snip out more maths...
The energy isn’t actually coming down the wires, but from the space surrounding the capacitor.
... snip out more maths ...
But it tells us a peculiar thing: that when we are charging a capacitor, the energy is not coming down the wires; it is coming in through the edges of the gap. That’s what this theory says!
I am not sure how you manage to reconcile these:Quote from: AnalogueLove1867But an electric field can't exist without an initial movement of charged particles in order to establish a potential difference.
How about the fact that this statement is wrong. Static electric fields exist, period. No movement required. The moment the wire is connected to the battery, there is a non-zero electric field in the wire.QuoteandQuotepushes against the next electron via their negative electric fields
It's a kind of chicken and egg situation: you can't have a field until something moves, but that movement is initiated by a field?
Someone is getting their fields crossed (pun intended).
The energy isn’t actually coming down the wires, but from the space surrounding the capacitor.
But it tells us a peculiar thing: that when we are charging a capacitor, the energy is not coming down the wires; it is coming in through the edges of the gap. That’s what this theory says!
As another example, we ask what happens in a piece of resistance wire when it is carrying a current. Since the wire has resistance, there is an electric field along it, driving the current.
...
There is a flow of energy into the wire all around. It is, of course, equal to the energy being lost in the wire in the form of heat. So our “crazy” theory says that the electrons are getting their energy to generate heat because of the energy flowing into the wire from the field outside. Intuition would seem to tell us that the electrons get their energy from being pushed along the wire, so the energy should be flowing down (or up) along the wire. But the theory says that the electrons are really being pushed by an electric field, which has come from some charges very far away, and that the electrons get their energy for generating heat from these fields. The energy somehow flows from the distant charges into a wide area of space and then inward to the wire.
Now we take another example. Here is a rather curious one. We look at the energy flow in a capacitor that we are charging slowly. (We don’t want frequencies so high that the capacitor is beginning to look like a resonant cavity, but we don’t want dc either.) Suppose we use a circular parallel plate capacitor of our usual kind, as shown in Fig. 27–3. There is a nearly uniform electric field inside which is changing with time. At any instant the total electromagnetic energy inside is u times the volume.
... snip out the maths ...
So there must be a flow of energy into that volume from somewhere. Of course you know that it must come in on the charging wires—not at all! It can’t enter the space between the plates from that direction, because E is perpendicular to the plates; E×B must be parallel to the plates.
... snip out more maths...
The energy isn’t actually coming down the wires, but from the space surrounding the capacitor.
... snip out more maths ...
But it tells us a peculiar thing: that when we are charging a capacitor, the energy is not coming down the wires; it is coming in through the edges of the gap. That’s what this theory says!
Looking forward to know how the energy travels from the battery to the wires if is not carried by the electrons (charged particles) moving inside the wire.
What is the name of the field that supplies the energy to the wires ?
How will the field know to deliver 9x more energy to one wire than the other physically identical wire ?
What is the field intensity and frequency?
Looking forward to know how the energy travels from the battery to the wires if is not carried by the electrons (charged particles) moving inside the wire.The same way electrical energy works in a capacitor or a transformer winding, or electromagnetic radiation. Charge doesn't 'carry' the energy, if they did, capacitors and transformers wouldn't work, because no charge is transferred.What is the name of the field that supplies the energy to the wires ?A decent wire has minimal energy 'supplied' to it.
But if you are asking what "What is the name of the field that supplies the energy to resistor?" it's the electric and magnetic fields. They even have their own Wikipedia pages:
https://en.wikipedia.org/wiki/Electric_field (in the context of "It also refers to the physical field for a system of charged particles")
https://en.wikipedia.org/wiki/Magnetic_fieldQuoteHow will the field know to deliver 9x more energy to one wire than the other physically identical wire ?For any decent wire it will be 'delivering' minimal energy to the wire - so it doesn't have to know anything!QuoteWhat is the field intensity and frequency?Some guy called Maxwell made up some equations that you can use to model them, by extending the work of Gauss, Ampère and Faraday.
Those equations are also famous enough to have their own Wikipedia pages: https://en.wikipedia.org/wiki/Maxwell%27s_equations
Richard Feynman would agree with this.
Notice how many times he emphasizes that it is "nuts" and a "theory". He said it four times on that page.
However Veritasium is never worth listening to. Veritasium is a joke.
Looking forward to know how the energy travels from the battery to the wires if is not carried by the electrons (charged particles) moving inside the wire.The same way electrical energy works in a capacitor or a transformer winding, or electromagnetic radiation. Charge doesn't 'carry' the energy, if they did, capacitors and transformers wouldn't work, because no charge is transferred.What is the name of the field that supplies the energy to the wires ?A decent wire has minimal energy 'supplied' to it.
But if you are asking what "What is the name of the field that supplies the energy to resistor?" it's the electric and magnetic fields. They even have their own Wikipedia pages:
https://en.wikipedia.org/wiki/Electric_field (in the context of "It also refers to the physical field for a system of charged particles")
https://en.wikipedia.org/wiki/Magnetic_field
For any decent wire it will be 'delivering' minimal energy to the wire - so it doesn't have to know anything!
Some guy called Maxwell made up some equations that you can use to model them, by extending the work of Gauss, Ampère and Faraday.
Those equations are also famous enough to have their own Wikipedia pages: https://en.wikipedia.org/wiki/Maxwell%27s_equations
Richard Feynman would agree with this.Can you ask him please? I too would love to know if he agrees with you.Quote
Notice how many times he emphasizes that it is "nuts" and a "theory". He said it four times on that page.
Yes, it sounds 'nuts' because it is counter-intuitive, but when a physicist uses the word theory they do not mean an unsubstantiated hunch.QuoteHowever Veritasium is never worth listening to. Veritasium is a joke.Veritasium isn't a physics lecture, it is infotainment. Parth G is more my style...
What I am saying isn't a theory ( it is well established fact ).
And it isn't a unifying field theory of everything.
Likewise, nobody has ever produced a unifying field theory and I doubt that it is even possible.
It could be just as futile as trying to create a perpetual energy machine.
Perpetual motion machine means only eliminating friction and at microscale that is possible as a current flow (electron stream) can be sustained forever (as far as we can measure) in a superconductor.
So a closed loop of superconductor wire in which you induce an electrical current will be maintained forever (at least we can not measure any reduction in current).
But if you check Veritasium video about the Faster than wind direct downwind vehicle you will see him basically claiming not perpetual motion but much worse overunity.
He claims vehicle can drive forever faster than wind in the same direction which will mean overunity but he can not understand even that is what he is saying.
It is worse that an university physics professor lost 10K as it was unable to explain how the vehicle works.
I tried to explain that vehicle has an energy storage device (the propeller) that creates a pressure differential (air is a compressible fluid) and that stored energy is what allows vehicle to just temporarily exceed wind speed.
They just made incomplete tests and drawn wrong conclusions about what they were seeing and even changed well known equations to fit what they think they saw.
That video, especially the second one where he doubled down by showing a University professor incapable to understand how it works lose the argument and bet gave me PTSD.
I just imagined smart young people failing to get in to university because the solved correctly this problem and the professors failing them.
And yes this exact problem was present in US at least in physics competitions.
You will think that access to all this information will make the society smarter overall but it seems that wrong information travels and spreads much faster and people do not have the time to think.
I just watched your video analysis of the blackbird faster-than-wind device. Cheers .
Although there is no resistance in superconductors, They don't maintain superconductivity forever due to the
interference of outside magnetic fields over time ( apparently from stuff I've read). So although they are extremely efficient, they still require some energy
to 1) maintain the low temperature obviously and 2) Top up the Current every now and then.
Out of curiosity I tried to find an article about superconductors running continuously with no current top-up for years and couldn't find anything.
Petrol stored in a shed would be a better long term energy storage solution than a superconducting loop.
Theoretically a Vacuum capacitor would also retain its charge forever. But knowing how the world works that wouldn't be true.
Although there is no resistance in superconductors, They don't maintain superconductivity forever due to the
interference of outside magnetic fields over time ( apparently from stuff I've read). So although they are extremely efficient, they still require some energy
to 1) maintain the low temperature obviously and 2) Top up the Current every now and then.
Out of curiosity I tried to find an article about superconductors running continuously with no current top-up for years and couldn't find anything.
Petrol stored in a shed would be a better long term energy storage solution than a superconducting loop.
Theoretically a Vacuum capacitor would also retain its charge forever. But knowing how the world works that wouldn't be true.
If there is no resistance (equivalent with no friction) then nothing can slow down the flow of electrons in an isolated system. You can shield the system form outside influence.
I'm not an expert in superconductivity, superfluids or most things related to quantum mechanical properties.
It seems super conductivity and superfluids have quite a bit in common. Here is a short video about superfluids
QuoteIn the SPICE simulation you do not define the length of the wire
You're a piece of work, eh. The wires are virtually non-existent. Zero length, as close as you can make them. Even if they were 10ft long (3m and a bit for the EU) whatever effect they could have would be NOTHING compared to the 1W burned up by the resistor, not the 1V of the supply.
It seems that you cannot actually answer the question and instead just go off on the slightest thing as a diversion.
I answered your question but maybe you missed the replay. Or you only read the first row of my replays as some others are doing.
https://www.eevblog.com/forum/chat/electroboom-how-right-is-veritasium!-dont-electrons-push-each-other/msg4277425/#msg4277425
the terminal will push extra electrons into the object creating an overall negative charge.
Quotethe terminal will push extra electrons into the object creating an overall negative charge.
What pushes them?
Quotethe terminal will push extra electrons into the object creating an overall negative charge.
What pushes them?
The chemical reaction in the battery cells which generates moving ions that release electrons to the cathode and subtract them from the anode.
This means that there is now more electrons than protons in the negative terminal and more protons than electrons in the positive terminal. Thus a potential difference is generated.
I am not sure how you manage to reconcile these:Quote from: AnalogueLove1867But an electric field can't exist without an initial movement of charged particles in order to establish a potential difference.
How about the fact that this statement is wrong. Static electric fields exist, period. No movement required. The moment the wire is connected to the battery, there is a non-zero electric field in the wire.QuoteandQuotepushes against the next electron via their negative electric fields
It's a kind of chicken and egg situation: you can't have a field until something moves, but that movement is initiated by a field?
Someone is getting their fields crossed (pun intended).
Wow, people here are an interesting bunch. If you connect any insulated metallic object to a minus 9v terminal, the terminal will push extra electrons into the object creating an overall negative charge.
When you disconnect the terminal the object will retain its charge because there is no way for the extra electrons to escape to an area with a lower concentration of electrons.
When you discharge the metallic object a small measurable current will pass from the object to ground. That is the extra electrons flowing from the object to ground. The object then returns to a 0 potential.
All conductors have some capacitance. It isn't just capacitors.
No, there is no chicken and the egg situation. In every example you can possibly give, it is a forced movement of charged particles with mass that produces a macroscopic potential difference in electronics.
The energy required to move electrons can come from chemical reactions, thermal energy, Nuclear bombardment, Radioactive decay, macroscopic motion ( turboelectric generators ), compression ( piezo-electrics) etc
Someone is getting their fields crossed (pun intended).
Wow, people here are an interesting bunch. If you connect any insulated metallic object to a minus 9v terminal, the terminal will push extra electrons into the object creating an overall negative charge.
When you disconnect the terminal the object will retain its charge because there is no way for the extra electrons to escape to an area with a lower concentration of electrons.
When you discharge the metallic object a small measurable current will pass from the object to ground. That is the extra electrons flowing from the object to ground. The object then returns to a 0 potential.
All conductors have some capacitance. It isn't just capacitors.
No, there is no chicken and the egg situation. In every example you can possibly give, it is a forced movement of charged particles with mass that produces a macroscopic potential difference in electronics.
The energy required to move electrons can come from chemical reactions, thermal energy, Nuclear bombardment, Radioactive decay, macroscopic motion ( turboelectric generators ), compression ( piezo-electrics) etc