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Require help with electron flow in a circuit, and when the wavelength is much longer than the size of the circuit.

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Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

In circuit we have currents and voltages. AC current flow through wire conductor let's say with speed of ligth. On 10cm target it will arrive after 33.333ps at the end of 1km wire it will arrive after delay of 3.333us. After it arrive on target it behaves like ordinary sine wave started at t=0.

from physics s=v*t
path equals speed*time

there must be conductive path between two points for current to flow in between
 
Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

You are imagining a problem that doesn't exist.

You previously asked
how do you generate a sin wave 100khz in small circuit?
Click to expand...
volker@muehlhaus answered the question very detailed. But you seem to adhere to the idea that a low frequency signal with a free space wavelength of 1 km, can't exist in a small circuit.

Wavelength has no meaning for the operation of a lumped element circuit. It only comes into play if you implement transmission lines in your circuit, or want to transmit a signal as radio wave.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

linuscomex said:
Please imagin this problem.
when sine wave propagate in circuit need Physical distance to propagate.
Click to expand...

No, the sine wave can go across all phases at one a fixed location. No distance needed, no propagation needed.

linuscomex said:
i ask you read wavelenght theory.
Click to expand...

Somehow some pages are missing in your text book.

linuscomex said:
My problem in 10cm physical distance how propagate 1 km distance?
Click to expand...

I does not get better if you repeat this again and again. Your question is wrong, because you ask "how does it do that". The answer is: it does not do that.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

linuscomex said:
Please imagin this problem.
when sine wave propagate in circuit need Physical distance to propagate. My problem in 10cm physical distance how propagate 1 km distance?
Click to expand...

Take a piece of rope as an example for a circuit. The rope has a finite length, say two meters. Tie the rope to an immovable object such that one end is stationary, and excite the other end manually. Keep the tension on the rope constant, the wave will always travel at the same velocity.

You can excite a wave on this rope. Moreover, you can excite this wave with any desired frequency, as fast as your hand will move. Since velocity is constant, the wavelength of the wave you are making will be different at all of these frequencies.

Can you excite the rope with a wave with a two meter wavelength? Yes.

Can you excite the rope with a wave with a half-meter wavelength? Probably, if you can move that fast.

Can you excite the rope with a wave with a two kilometre wavelength? This answer is undefined. The medium in which the wave propagates (the rope) is only two meters long. However, you can excite the rope with any arbitrarily low frequency.

Imagine exciting a wave on the rope that has a period of 10 seconds, or 0.1 Hz. Obviously, this is possible.

This is what a low frequency (e.g. 100 kHz) electromagnetic wave looks like inside of a 10 cm circuit.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

Borber said:
In circuit we have currents and voltages. AC current flow through wire conductor let's say with speed of ligth. On 10cm target it will arrive after 33.333ps at the end of 1km wire it will arrive after delay of 3.333us. After it arrive on target it behaves like ordinary sine wave started at t=0.

from physics s=v*t
path equals speed*time

there must be conductive path between two points for current to flow in between
Click to expand...

thanks very very much.
my friend I know one thing and that is that when you speack about wavelenght the wavelenght means :The covered distance by electron charge to complete one period.
in 10 cm lengh and wavelenght 1 kilometer electron charge covered distance 1 kilometer in 10 cm lengh and no lenght to produce complete 1 period. is it true???
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

What you consider as wavelength is a period of sine wave current. It is measured in seconds not meters. X axis on diagram is t time and not distance.

We have also a AC voltage that stays in place and does not travel or flow. AC voltage has also it's frequency and wave length the same 300kHz and 1km.

We are not talking about electromagnetic waves what you are confusing with currents or voltages in a 10cm circuit.

Even nowadays it is not known what are electromagnetic waves made from. We know how to make them while physics behind is still to be discovered.
 
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Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

linuscomex said:
when you speack about wavelenght the wavelenght means :The covered distance by electron charge to complete one period.
Click to expand...

:shock:

That's complete nonsense.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

Borber said:
What you consider as wavelength is a period of sine wave current. It is measured in seconds not meters. X axis on diagram is t time and not distance.

We have also a AC voltage that stays in place and does not travel or flow. AC voltage has also it's frequency and wave length the same 300kHz and 1km.

We are not talking about electromagnetic waves what you are confusing with currents or voltages in a 10cm circuit.

Even nowadays it is not known what are electromagnetic waves made from. We know how to make them while physics behind is still to be discovered.
Click to expand...
wavelength means: V/F and in space C/F so wavelength is there on conductor.
yes voltage not move but current move like domino. It is measured in meter so distance important but The only compelling reason to accept the 1 kilometer wavelength can produces in 10 cm length or less is when a sine wave with 1 kilometer wavelength or when full period of sine wave produced in circuit The distance is 1 kilometer automatically traveled by backward and forward electron charge and wavelength is not a distance between two point that not change but But it is the distance traveled is it true?
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

linuscomex said:
yes voltage not move but current move like domino.
Click to expand...

That's complete nonsense.
You start from a wrong concept (wavelength = travel distance for electrons) and that is why all conclusions are wrong.

linuscomex said:
But it is the distance traveled is it true
Click to expand...

No, wrong.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

Electromagnetic waves propagates in space through the air freely. Depending on radiator their space density or radiation pattern may have different shapes.
At very high frequencies a waveguide is used instead wires or coaxial cables in circuits. Waveguide is a square or round metal tube. There you can see your wave lengths but no currents or voltages. Energy still exists. Does it have corpuscular or wave nature or something else is still to be discovered. You may call it as ether.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

Borber said:
Energy still exists. Does it have corpuscular or wave nature or something else is still to be discovered. You may call it as ether.
Click to expand...

Wave or particle, a discussion during James C. Maxwell's time
https://rsta.royalsocietypublishing.org/content/366/1871/1771

I would say that linuscomex confusion is more trial, because he assumes that for any AC to exist, electrons must always travel one wavelength. He simply does not understand that AC has a period in both time and distance.

For him, electrons must always travel over the distance of one wavelength. That's where he gets lost, because his starting point is already wrong.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

This question has a counterpart at the other end of the frequency spectrum.

At 12 GHz, the wavelength is only an inch. What is the physical size that circuitry be made, until it is unable to operate at such speeds?

I try but I have trouble imagining how to construct such an oscillator with discrete components. Distances become large enough to contain an entire wavelength or two.

Components which operate at such frequencies need to be teeny-tiny. Wiring needs to be very short. I wonder if the resonant frequency is then determined by the length of a wire, rather than by the values of components?

I have heard they hope to solve these problems by developing optical computers.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

Read about dielectric resonator oscillator. Each satellite LNB has one.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

volker@muehlhaus said:
That's complete nonsense.
You start from a wrong concept (wavelength = travel distance for electrons) and that is why all conclusions are wrong.



No, wrong.
Click to expand...

You can just say (That's complete nonsense. ) and I'm sorry for you because you do not have an explanation for this phenomenon.
you say ac has a period in time and distance.where is the distance in circuit? ??Do you have a definition of distance?
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

Now it is safe to pick up definition from Wiki.
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

linuscomex said:
you say ac has a period in time and distance.where is the distance in circuit? ??
Click to expand...

As discussed above many times: No distance is needed. If the distance is zero, then you only see a change of voltage/current over time. And if there is a distance, the voltage/current at these locations have some time delay. The time delay can be anything from 0 to infinity, depending on distance.
 
Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

volker@muehlhaus said:
As discussed above many times: No distance is needed. If the distance is zero, then you only see a change of voltage/current over time. And if there is a distance, the voltage/current at these locations have some time delay. The time delay can be anything from 0 to infinity, depending on distance.
Click to expand...

Thats wright.
I say your above sentence in difference means.
If distance on conductor have same value of wavelength time delay happen because time neded to complete one period is the same with time to propagte this distance.
And when wavelenght very big from length of conductor the delay not happen.
I say no distance need to complete one period of ac signal. But whay? Because distance in this case means sum of electron charge traveled .if your distance 10 cm and wavelength 1 kilometer the time to propagate in 10 cm very very less than time to complete period and in period the sum of traveled 10 cm is 1kilometer because in time period, charge electron can backward and forward 100000 times and asum of this times is 1 kilometer.
if wavelength 1 kilimeter and your circuit is 1 kilometer this times is 1 and distance 1 kilometer.is it true?
 

Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

One obvious nonsense at first sight is that distance is is sum of electron charge traveled. Traveling electron charges are electric current. Current strength or amplitude is proportional to sum of charges traveling no matter how long is conductor.
In time of the first period of sinus current it is dead time for the 1km distant point on straight wire. Nothing happens in that time. Yes this point would be a wave length apart from the start but along the wire. Start and end points can be only 1mm apart physically. After that time current in this point starts to flow from t=0 like at beginning of wire. Such behaviour there could be many in a circuit we call transition time as a difference to steady state behaviour. First happens after switch on and last until stable behaviour is reached.
 
Re: electron flow in circuit, when wavelength is very longer than size of circuit ?

linuscomex said:
If distance on conductor have same value of wavelength time delay happen because time neded to complete one period is the same with time to propagte this distance.
Click to expand...

No. Time delay happens because time delay happens.
Time delay also happens for pulses and any other signal, and depends only on distance and propagation speed.
The difference in phase is only a result of time delay. And dependent on length, the delay can cause a 1° shift or 360° shift or something else.

linuscomex said:
And when wavelenght very big from length of conductor the delay not happen.
Click to expand...

Wrong. If you have a distance, you have a time delay, for any wavelength.

linuscomex said:
Because distance in this case means sum of electron charge traveled .if your distance 10 cm and wavelength 1 kilometer the time to propagate in 10 cm very very less than time to complete period and in period the sum of traveled 10 cm is 1kilometer because in time period, charge electron can backward and forward 100000 times and asum of this times is 1 kilometer.
Click to expand...

No, WRONG.
Your picture of physics and currents and electrons is WRONG.
You do not need to repeat it again and again.
It is WRONG.

Of course, electron (or current) direction changes with frequency, independent of the wire length.
 
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