Let υd be the drift velocity.
Electric field produced inside the wire is
E = V/l ………… (i)
Force on an electron, a = — Ee
Acceleration of each electron a= -Ee/m
[ from Newton’s law, a = F/m]
where m is mass of electron.
Velocity created due to this acceleration = Ee/m τ
where τ is the time span between two consecutive collisions. This ultimately becomes the drift velocity in steady-state.
We know that current in the conductor i = neAυd (where, n is number of free electrons in a conductor per unit volume)
This is Ohm’s law.
