Q. When a potential difference is applied across a conductor, the free electrons in the conductor are set into motion. Two velocities are associated with the moving electron-the drift velocity and average velocity. The fact is that the two are :

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A

Entirely different

B

Same

C

Same in some conductors and different in others

D

None of the above

Solution:

Drift velocity of electrons is the terminal velocity of electrons motion in presence of external electric field force which is balanced by the opposing force on electrons due to their thermal agitation where as average velocity of electrons in a conductor is defined only by their thermal motion like gas molecules in a gas in their random motion.

Questions from Current Electricity

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For which of these junctions, is the following equation correct ?
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