Relating Movement of Electrons in Currents to Wire Movement/Energy/Power

In summary, according to the article, a very light wire can transmit very high currents and may be able to cause a visible movement in the wire due to the initial acceleration of the electron flow. Also, it is important to note that the energy/power of electrons is transferred via movement of charges, and a static electric system may contain electrical energy but this can only 'flow' in a dynamic system.
  • #1
Islam Hassan
233
5
Off the Wikipedia:

"...in a copper wire of cross-section 0.5 mm2, carrying a current of 5 A, the drift velocity of the electrons is on the order of a millimetre per second."

Suppose we have a setup with a very very light wire which can transmit very very high currents. Once the current is switched on, can we detect a visible movement in the wire due to the initial acceleration of the electron flow (due to F=MA) within it?

Another question is taking into account electron density in a conducting copper wire, can we relate the electron speed to the energy/power provided by the wire taking into account E= 0.5mv^2?

IH
 
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  • #2
Islam Hassan said:
Suppose we have a setup with a very very light wire which can transmit very very high currents. Once the current is switched on, can we detect a visible movement in the wire due to the initial acceleration of the electron flow (due to F=MA) within it?
I would have to work it out to be sure, but my guess would be yes.

Islam Hassan said:
Another question is taking into account electron density in a conducting copper wire, can we relate the electron speed to the energy/power provided by the wire taking into account E= 0.5mv^2?
No. I have worked this out before, the KE of the electrons is an insignificant fraction of the power delivered to a wire.
 
  • #3
DaleSpam said:
I would have to work it out to be sure, but my guess would be yes.

No. I have worked this out before, the KE of the electrons is an insignificant fraction of the power delivered to a wire.

Then in what form is the (bulk of the) energy/power of electrons transmitted in an electric current? Vibration/wiggling of electrons or something else?

IH
 
  • #4
Electrical energy is electrical and magnetic. It depends on voltage and charge movement. You can see that in the equations.

Also, judging by the mass difference between an electron and a proton/neutron pair, I'd say the kinetic energy/force would be negligible.
 
  • #5
russ_watters said:
Electrical energy is electrical and magnetic. It depends on voltage and charge movement. You can see that in the equations.

Also, judging by the mass difference between an electron and a proton/neutron pair, I'd say the kinetic energy/force would be negligible.

Ok, understood.

Can we however say that electrical energy can only be extracted from a system via movement of electrons or changes in an electric field? That a static electical system may well contain electrical energy but that this can only 'flow' in a dynamic system?

Kinetic energy of electrons may be too weak to matter much, but I think that a dynamic system is essential to transmission of electrical energy.

IH
 
  • #6
Islam Hassan said:
Can we however say that electrical energy can only be extracted from a system via movement of electrons or changes in an electric field?
Yes. The movement of charges is called a current and is represented by the symbol j. In Poynting's theorem, the energy transferred to matter from the EM fields is given by E.j, so as you say, energy can only be extracted via movement of charges in the presence of an electric field.
 
  • #7
Islam Hassan said:
Ok, understood.

Can we however say that electrical energy can only be extracted from a system via movement of electrons or changes in an electric field? That a static electical system may well contain electrical energy but that this can only 'flow' in a dynamic system?

Kinetic energy of electrons may be too weak to matter much, but I think that a dynamic system is essential to transmission of electrical energy.

IH
Sure, but note again that it is the charge that matters. Ie, a moving proton and a moving electron carry the same charge even though the proton is 1800 times more massive.
 

1. How does the movement of electrons in a wire create energy?

The movement of electrons in a wire creates energy through a process called electrical current. When a voltage or potential difference is applied to a wire, it causes electrons to flow from a higher potential to a lower potential. This flow of electrons generates a flow of energy, known as electrical energy, which can be harnessed and used to power devices.

2. How is the movement of electrons related to the movement of a wire?

The movement of electrons in a wire is directly related to the movement of the wire itself. As electrons flow through a wire, they collide with the atoms and molecules of the wire's material, causing the wire to vibrate. This vibration creates movement in the wire, which can be harnessed to power devices or create other forms of energy.

3. What is the difference between current, voltage, and power?

Current, voltage, and power are all related to the movement of electrons in a wire, but they represent different aspects of this movement. Current is the measurement of the rate at which electrons are flowing through a wire. Voltage is the measurement of the difference in electrical potential between two points, which drives the flow of electrons. Power is the rate at which energy is being transferred by the flow of electrons.

4. How does the resistance of a wire affect the movement of electrons?

The resistance of a wire is a measure of how difficult it is for electrons to flow through the wire. Higher resistance means that there is more obstruction to the flow of electrons, which can slow down the movement of electrons and decrease the amount of current that can flow through the wire. This can also result in the wire heating up as more energy is needed to overcome the resistance.

5. Can we control the movement of electrons in a wire to increase or decrease energy/power output?

Yes, the movement of electrons in a wire can be controlled through various means, such as using different materials for the wire, changing the voltage or potential difference, or adding components like resistors to increase or decrease the flow of electrons. By controlling the movement of electrons, we can also control the amount of energy and power output from a wire, making it possible to regulate and optimize its usage in different applications.

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