Explain the relation between current and drift velocity.

Relation between Current and Drift Velocity

  • The electrons move with an average velocity that is independent of time, although electrons get accelerated.
  • This is because an electron suffers collisions with heavy fixed ions, however, after the collision, it will emerge at the same speed in random directions.
  • This average velocity of electrons is known as the drift velocity.

The relation between current and drift velocity is,

I = neAvd

  • where, n refers to the number of free electrons per unit volume,
  • e is the charge of an electron,
  • A is the planar area located inside the conductor.

Related Questions

  1. Give two examples of drift velocity.
  2. What is the relation between drift velocity and electric field?
  3. 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.
  4. What Are Two Kinds Of Electricity?
  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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                      CBSE CLASS XII Previous Year Papers

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