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Define the terms (i) drift velocity, (ii...

Define the terms (i) drift velocity, (ii) relaxation time. A conductor of length L is connected to a d.c. source of emf `epsi.` If this conductor is replaced by another conductor of same material and same area of cross-section but of length 3L, how will the drift velocity change ?

Text Solution

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Drift velocity : The average velocity with which the free electrons drift under the influence of an external field.
Relaxationk time: Average time interval between two succesive collisions of an electron with the ions/atoms of the conductor.
The drift velocity will be inversely proportional to (or `v _(d) prop (1)/(I))` and hence it will become and third of its initial value.
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