Question

Define drift velocity and find expression for it

Answer 1

Drift velocity is defined as the average velocity with the free electrons get drifted towards the positive end of the conductor under the influence of an external electric field applied

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Answer 2

a drift velocity is the average velocity attained by charged particles, such as electrons, in a material due to an electric field. In general, an electron in a conductor will propagate randomly at the Fermi velocity, resulting in an average velocity of zero.