b) Mean drift velocity

a) mean drift velocity of charge carriers

b) I = Anev where n is the number density of charge carriers

mean drift velocity = the net velocity of electrons moving through a conductor

I = Anev

• electric current (A) = cross-sectional area of the conductor (m²) × number density (m^-3) × elementary charge × velocity (ms^-1)

v ∝ 1/A