Define mobility of electron.

The drift velocity of an electron for a unit electric field is referred to as the mobility of the electron. The mobility of an electron can be calculated by the formula:

μ = Vd/E

where, Vd refers to the drift velocity of an electron

E is the external electric field

The SI unit of electron mobility is m2s-1V-1


Related Questions

  1. Give two examples of drift velocity.
  2. What is the relation between drift velocity and electric field?
  3. Explain the relation between current and drift velocity.
  4. Define the drift velocity of electrons in a conductor?
  5. Define relaxation time of the free electrons drifting in a conductor? How is it related to the drift velocity of free electrons? Use this relation to deduce the expression for the electrical resistivity of the material.
  6. 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.
  7. 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.

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CBSE CLASS XII Related Questions

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                        CBSE CLASS XII Previous Year Papers

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