How Small drift speed of electron causes high-speed electric current?
Last updated on April 14th, 2021 at 12:32 pm
Most charge carriers, like electrons, move slowly. Free electrons repeatedly collide with the positive metal ions as they drift through the wire towards the positive terminal. The reason that electric current flow so quickly is that all the free electrons in the wire start moving almost at once. Now let’s see how the Small drift speed of electrons causes a high-speed electric current.
Most electrical signals carried by currents travel at speeds on the order of 10^8 m/s, a significant fraction of the speed of light.
Interestingly, the individual charges that make up the current move much more slowly on average, typically drifting at speeds on the order of 10−4 m/s.
In other words, When charged particles are forced into this volume of a conductor, an equal number are quickly forced to leave. In other words, when a free charge is forced into a wire, the incoming charge pushes other charges ahead of it, which in turn pushes on charges farther down the line.
The repulsion between like charges makes it difficult to increase the number of charges in a volume. Thus, as one charge enters, another leaves almost immediately, carrying the signal rapidly forward. The resulting electrical shock wave moves through the system at nearly the speed of light.
Thus, a small drift speed of electron causes the high-speed electric current.
Related study:
1) Derive the relation between current and drift velocity
2) Numerical problems based on drift velocity of electron and electric current | solved