# What is the relation between drift velocity and electric field?

Mobility m is the magnitude of drift velocity per unit electric field.

m = |Vd |/E = qt/ m

The S.I unit of mobility is m2/Vs. Mobility is a positive quantity.

Vd = mE

The above equation is the relation between drift velocity of an electron and the applied electric field.

Drift velocity varies with the intensity of the electric field and is given by the formula:

$$\begin{array}{l}V_{d}\propto E\end{array}$$