Electric Current: Why Does It Flow at Light Speed?

In summary, the speed of electric current is equal to the speed of light because the electric field that carries the current travels at the speed of light, while the electrons themselves have a much slower drift velocity. This is due to the properties of copper wire, where the drift velocity of electrons is only a few km/s.
  • #1
asad1111
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why electric current flows at speed of light when we know that current is due to the drift velocity of electron which is only few km/s(i think)?
 
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  • #2
hi asad1111! :smile:
asad1111 said:
why electric current flows at speed of light when we know that current is due to the drift velocity of electron which is only few km/s(i think)?

no, the electric field travels (away from the electrons) at the speed of light

the electrons themselves get left behind! :biggrin:
 
  • #3
asad1111 said:
... we know that current is due to the drift velocity of electron which is only few km/s(i think)?

The drift velocity of electrons in copper wire is
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http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmmic.html
 

FAQ: Electric Current: Why Does It Flow at Light Speed?

1. What is electric current?

Electric current is the flow of electric charge. It is measured in amperes (A) and represents the rate at which electric charge flows past a given point in a circuit.

2. Why does electric current flow at the speed of light?

Electric current is made up of moving electrons, which travel at near the speed of light. However, the actual speed of the electric current depends on the medium it is flowing through. In a vacuum, electric current can travel at the speed of light, but in a conductor, it is much slower due to collisions with atoms and other obstacles.

3. What factors affect the speed of electric current?

The speed of electric current is affected by the type of material it is flowing through, the temperature of the material, and the strength of the electric field. In general, electric current travels faster in materials with low resistance and at higher temperatures.

4. Can electric current travel faster than the speed of light?

No, electric current cannot travel faster than the speed of light. According to Einstein's theory of relativity, nothing can travel faster than the speed of light in a vacuum. Even though the electrons that make up electric current can travel at near the speed of light, the overall speed of the current is limited by the medium it is flowing through.

5. How is electric current related to electromagnetism?

Electric current and electromagnetism are closely related. When electric current flows through a wire, it creates a magnetic field around the wire. This is the principle behind electromagnets and is the basis for many technologies, such as electric motors and generators.

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