How do we explain powering a load without converting any current?

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Thread Starter

Mark Flint

Joined Jun 11, 2017
145
hi Mark,
Read this battery link.
Your understanding of voltage potential and current flow is way off mark.
The Electrons don't get used up or changed in any way, its a chemical disassociation and recombination process within the battery.
ie: electron movement from one plate to another plate within the battery via the electrolyte.
E
https://web.mst.edu/~gbert/BATTERY/battery.html
Thanks for the link. Yes I think it's well established even in this thread that electrons don't get used up or changed. In the specified terms in your link, an oxidation--reduction reaction is taking place with the load in between. One plate loses an electron, the other gains one. Apart from terminology I'm not sure how this contradicts what I said. Also in the linked piece, "The current is directly related to the rate at which electrons are pumped through the wire and any resistances in the circuit." Are electrons really being "pumped through the wire"?
 

ElectricSpidey

Joined Dec 2, 2017
3,349
My formal education of electronics started with the electron, and never lead to any confusion...all of my confusion with electronics started with the internet.

Example:

The link in #41...all of the talk is about fields and energy, and is all well and good but then at the bottom of the page the image is suddenly describing the flow of "power" well I learned that "power" is a product and is "produced" at any given point in a circuit, mostly at the load...and does not flow in a circuit.

So my advice to the OP is if you want to learn about electric theory and electronics, take a formal instruction class and avoid the web like the plague.
 

BobTPH

Joined Jun 5, 2013
11,607
There is the same amount of belt like there is the same amount of current before and after the load.
The belt is not analogous to current. The speed of the belt is analogous to current. Just like the speed of the belt after the pulley cannot be different than the speed of the belt before the pulley, the current into the lamp cannot be different than the current out.

In fact, the analogy is even better that this. The tension in the belt is lessened after the pulley if the belt is doing work, just as the voltage is lowered in the electrical case. Look up the German word Spannung. It means either voltage or tension in English!

Bob
 

Thread Starter

Mark Flint

Joined Jun 11, 2017
145
OK Bob thanks. When I think of current I sometimes see it as movement (flow) of electrons. But sometimes I see a current as a the energy of the electron that is transferred in the same way as Newton's Cradle transfers it. It's funny how many opinions there are on this matter. I think there's still enough mystery in it for even the experts to be less dogmatic.
 

Thread Starter

Mark Flint

Joined Jun 11, 2017
145
Hi Mark,
There is no mystery in this electron current flow technology topic, it is simply a lack of understanding on your part of the available proven information.

No offence intended.
E
No offence taken. But the mystery I'm talking about is not electron flow theory. The mystery for me is how the electron transfers energy to the load, as per my original question. No one here has tried to answer that, but instead points me off to get further formal education. So I'm still hoping for an answer, or at least a discussion on the possibilities.
 

nsaspook

Joined Aug 27, 2009
16,410
My formal education of electronics started with the electron, and never lead to any confusion...all of my confusion with electronics started with the internet.

Example:

The link in #41...all of the talk is about fields and energy, and is all well and good but then at the bottom of the page the image is suddenly describing the flow of "power" well I learned that "power" is a product and is "produced" at any given point in a circuit, mostly at the load...and does not flow in a circuit.

So my advice to the OP is if you want to learn about electric theory and electronics, take a formal instruction class and avoid the web like the plague.
I started in electronics with the electron (I worked on tons of tube gear including digital tube devices) too so I can see the shortcoming of that type of education unless you expand to a deeper understanding.

Your example shows a shallow understanding of electrodynamics.
https://opentextbc.ca/universityphysicsv2openstax/chapter/energy-carried-by-electromagnetic-waves/

Power is simply the rate of the EM field energy being transferred. Power don't appear from empty space from point A to point B so it must 'get' there by a flow of something.

When you stand outdoors in the sunlight, you feel the energy that the sunlight carries.
 
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nsaspook

Joined Aug 27, 2009
16,410
No offence taken. But the mystery I'm talking about is not electron flow theory. The mystery for me is how the electron transfers energy to the load, as per my original question. No one here has tried to answer that, but instead points me off to get further formal education. So I'm still hoping for an answer, or at least a discussion on the possibilities.
It's easy. THE ELECTRON DOES NOT TRANSFER ELECTRICAL ENERGY TO THE LOAD!!!!

I've said this over and over, you're not listening.
 

Deleted member 115935

Joined Dec 31, 1969
0
Even a cursory reading of the history of science would warn against this, wouldn't you agree?
You are mixing definitions here, I must admit when I was new to this I wondered the same.

First rule to learn is current around a circuit is constant. current into a object is same as current out, kirchofs law,

so if battery is delivering say 1 amp, it will also have one amp going into it.
Easy to demonstrate , put the test meter anywhere in the circuit to meassure current, and it will be same.

Next the voltage around the circuit , will drop as you follow the current around.
Again easy to demonstrate,
put the -ve terminal of the meter on the negative of the battery, this is you referance, using the positive probe, meassure the voltage around the circuit,
The maximum voltage will be at the +ve of the battery,

Last, the light / heat, This is energy, Joules.
1 joule is 1 watt per second,
and a watt is volts times amps

As you have demonstrated, the current is constant, but the voltage across then bulb is dropped,,
so you have a change in power / or another way joules.

There is nothing more to it than that


so to answer your question
How do we explain powering a load without converting any current

As you have seen, there can not be a change in current in your example,
there is a change of volts,
which as you have seen, with current , that is watts,
and watts are joules per seconds, which is power.
 

nsaspook

Joined Aug 27, 2009
16,410
I hear you loud and clear explaining what is NOT happening ;-)
Once you accept this then the task to to discover what's really happening if you want a clear microscopic EM view of a circuit. Just to be clear, the microscopic EM view of the interaction of charge carriers and fields of a circuit is not necessary to solve problems in circuit theory because we have lot's of tricks to mitigate electromagnetic coupling effects with components (filters) and practices (shielding, twisting and grounding) that allow the assumptions (zero length conductor) of circuit theory to still be true.
Three basic assumptions permit us to use circuit theory, rather than electromagnetic field theory, to study a physical system represented by an electric circuit.
These assumptions are as follows:
Electrical effects happen instantaneously throughout a system.
The net charge on every component in the system is always zero.
There is no magnetic coupling between the components in a system.
http://fehmibardak.cbu.edu.tr/wp-content/uploads/2017/09/Lecture1_Circuit-Variables.pdf
 

nsaspook

Joined Aug 27, 2009
16,410
REALLY?
So the electrons don't go through a resistance, casing the atoms to vibrate at a higher rate and raising the resistor's temperature, thus transferring energy?
Really, I said ELECTRICAL ENERGY.

Electrons don't change their charge or mass when going through a resistor. What happens is we have high electron accelerations from the electric field across that resistor and very low electron accelerations across the wiring good conductors elements
Transferring energy? That's KE from the acceleration of the electron using electric field energy. That KE causes 'vibrations' at a higher rate and raising of the resistor's temperature.

https://brilliant.org/wiki/heat-dissipated-by-resistors/
Resistors plays a major role in reducing the current in circuits and therefore protecting circuits from damage resulting from overdraw of current by dissipating the kinetic energy of electrons in current as thermal energy (heat). This is what allows electricity to be useful: the electrical potential energy from the voltage source is converted to kinetic energy of the electrons, which is then transferred to something we wish to power, such as a toaster or a laptop.
This transformation happens at the load as field energy travels from the source to load on all conductors. This field energy (per the Poynting vector ) then locally causes the acceleration of charges.
https://www.ece.k-state.edu/people/faculty/carpenter/documents/poynting.pdf
 
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Thread Starter

Mark Flint

Joined Jun 11, 2017
145
Richard Feynman figured that out in 1962, and got the Nobel Prize for it. Suffice to say, his paper on this is ... thick.

ak
Thanks for that. Ah, well now perhaps that's the problem. I didn't realise it, but the answer I'm looking for seems to have challenged the best minds in this field. I've just seen a quote by Jennifer Coppersmith on Feynman... "If Feynman says the concept of energy is difficult then you know it really is difficult." But figuring something out means something different to a theoretical physicist than an empirical guy. I've previously read a lecture he gave on electrostatics which I thought was good and easy enough to understand.
 

nsaspook

Joined Aug 27, 2009
16,410
Thanks for that. Ah, well now perhaps that's the problem. I didn't realise it, but the answer I'm looking for seems to have challenged the best minds in this field. I've just seen a quote by Jennifer Coppersmith on Feynman... "If Feynman says the concept of energy is difficult then you know it really is difficult." But figuring something out means something different to a theoretical physicist than an empirical guy. I've previously read a lecture he gave on electrostatics which I thought was good and easy enough to understand.
You don't need to understand the tiny details of QED to GROK the principles of energy flow in a circuit.

 

nsaspook

Joined Aug 27, 2009
16,410
Of course the fields don't exist by themselves, they are generated by the free electrons in the circuit.
Yes, but that is an effect of localized charge separation from some energy source, that energy source could be electromagnetic energy self propagating across space from far distant sources and currents or surrounding a wire in a simple circuit. It works as a system with each component doing an important part of the process.

To say they are generated at X time is one (classical) way to look at it but another way is to say the electromagnetic field (not the electric or magnetic fields) and electron field both have always existed in the circuit where particles are quantized excitations of the fields.

But that's another rathole.
https://en.wikipedia.org/wiki/Quantum_field_theory
 
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Thread Starter

Mark Flint

Joined Jun 11, 2017
145
Electrons don't change their charge or mass when going through a resistor. What happens is we have high electron accelerations from the electric field across that resistor and very low electron accelerations across the wiring good conductors elements
Transferring energy? That's KE from the acceleration of the electron using electric field energy. That KE causes 'vibrations' at a higher rate and raising of the resistor's temperature.
If you have different rates of electron acceleration in a circuit does that imply that current is flowing slower in the resistor than the copper wire?
 

nsaspook

Joined Aug 27, 2009
16,410
If you have different rates of electron acceleration in a circuit does that imply that current is flowing slower in the resistor than the copper wire?
Individual or group electron acceleration is a bit of a simplification in a conductor. What we have in more detail is a bias to the much faster random thermal velocity of the free electrons in the electron "sea". This slight bias in X direction is the drift velocity.

Current is a rate. In the good conductor more free electrons drift slower, in the resistor fewer free electrons drift faster, for the same rate.

We need to calculate the drift velocity in X conductor with X free electrons for for current.
https://courses.lumenlearning.com/austincc-physics2/chapter/20-1-current/
Electrical signals are known to move very rapidly. Telephone conversations carried by currents in wires cover large distances without noticeable delays. Lights come on as soon as a switch is flicked. Most electrical signals carried by currents travel at speeds on the order of 108 m/s, a significant fraction of the speed of light. Interestingly, the individual charges that make up the current move much more slowly on average, typically drifting at speeds on the order of 10−4 m/s. How do we reconcile these two speeds, and what does it tell us about standard conductors? The high speed of electrical signals results from the fact that the force between charges acts rapidly at a distance. Thus, when a free charge is forced into a wire, as in Figure 4, the incoming charge pushes other charges ahead of it, which in turn push on charges farther down the line. The density of charge in a system cannot easily be increased, and so the signal is passed on rapidly. The resulting electrical shock wave moves through the system at nearly the speed of light. To be precise, this rapidly moving signal or shock wave is a rapidly propagating change in electric field.
 
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