Nature & speed of electricity

AI Thread Summary
Electric current is viewed as a macroscopic quantity by electrical engineers, focusing on voltage and current, while quantum physicists consider it microscopic, dealing with individual electrons. The speed of electricity is not the same as the drift velocity of electrons, which is slow; instead, the electrical disturbance travels at 0.5 to 0.8 times the speed of light through a conductor. This means that while electrons move slowly, the signal or disturbance they create propagates quickly. Understanding these concepts requires distinguishing between macroscopic and microscopic perspectives. Clarifying these points can help resolve confusion about the nature and speed of electricity.
A AM ARYA
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1.Is electric current a microscopic or macroscopic quantity?I think it is macroscopic as we can feel it,but when I asked my friend he said it is microscopic as it deals with electrons.I'm a bit confused...
2.What is the speed of electricity?Is it equal to the drift velocity of electrons or the speed of light?
Please clarify my doubts...
 
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A AM ARYA said:
1.Is electric current a microscopic or macroscopic quantity?I think it is macroscopic as we can feel it,but when I asked my friend he said it is microscopic as it deals with electrons.I'm a bit confused...
2.What is the speed of electricity?Is it equal to the drift velocity of electrons or the speed of light?
Please clarify my doubts...

1) I have no idea what you are asking about here.

2) if I create an electrical disturbance at one end of a long wire (think of power lines crossing continents), the disturbance travels down the wire at 0.5 to 0.8 light speed, but the electrons drift hardly any distance.
 
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1) It depends on if your an electrical engineer or a quantum physicist. EEs treat electricity in macroscopic terms like voltage and current and don't worry about individual electrons or whatever (most of us anyway). Quantum physicists treat electrons and photons as individuals.

2) Both. Electrons move slowly. Photons move quickly. Both are electric have electrical qualities.
 
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