What is the relation between drift velocity and electric field?

Mobility m is defined as the magnitude of drift velocity per unit of an electric field. Therefore, 

m = |Vd|/E = qt/m

The SI unit used to represent mobility is m2/Vs. It is a positive quantity.

Vd = mE

This is the relation between the drift velocity of an electron and the applied electric field.

Drift velocity varies with the electric field intensity and is given by the formula \(\begin{array}{l}V_{d}\propto E\end{array}\)


Related Questions

  1. Give two examples of drift velocity.
  2. What Are Two Kinds Of Electricity?
  3. Why Potentiometer Is Preferred Over Voltmeter?
  4. Two conducting wires X and Y of the same diameter but different materials are joined in series across a battery. If the number density of electrons in X is twice that in Y, find the ratio of the drift velocity of electrons in the two wires.
  5. It is known that the drift velocity of electrons is only a few mm/s for a current of a few amperes. How is it possible that a current is established almost instantaneously when a circuit is closed? For example, a bulb glows as soon as the connection is switched on. Explain.

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