Electric Current: Why Does It Flow at Light Speed?

AI Thread Summary
Electric current flows at the speed of light due to the propagation of the electric field, not the actual movement of electrons. While the drift velocity of electrons in conductors like copper is relatively slow, typically only a few kilometers per second, the electric field influences the entire circuit almost instantaneously. This means that when a voltage is applied, the effect is felt throughout the conductor at light speed. The electrons themselves move much slower, but their collective movement creates the current. Understanding this distinction clarifies why electric current can be perceived as flowing at light speed.
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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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:​
 
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
 
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