The Drude model of electrical conduction was proposed in 1900 by Paul Drude to explain the transport properties of electrons in materials (especially metals). The model, which is an application of kinetic theory, assumes that the microscopic behavior of electrons in a solid may be treated classically and looks much like a pinball machine, with a sea of constantly jittering electrons bouncing and re-bouncing off heavier, relatively immobile positive ions.
The two most significant results of the Drude model are an electronic equation of motion,
and a linear relationship between current density and electric field ,
Here is the time and, and, and are respectively an electron's momentum, charge, number density, mass, and mean free time between ionic collisions. The latter expression is particularly important because it explains in semi-quantitative terms why Ohm's Law, one of the most ubiquitous relationships in all of electromagnetism, should be true.
The model was extended in 1905 by Hendrik Antoon Lorentz (and hence is also known as the Drude–Lorentz model) and was supplemented with the results of quantum theory in 1933 by Arnold Sommerfeld and Hans Bethe.
Read more about Drude Model: Assumptions, Accuracy of The Model
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