question_answer

Define drift velocity. Write the expression for the current in a conductor of cross-sectional area A in terms of drift velocity.

Answer:

Drift velocity (\[{{\text{v}}_{\text{d}}}\]) is defined as the average velocity with which the free electrons in a conductor get drifted towards the positive end of the conductor under the influence of an electric field applied across the conductor.

Expression for current, \[I=neA{{\text{v}}_{\text{d}}}\]

Where, \[n\] is the electron density in the conductor of cross-section area A.