Define the terms (i) drift velocity, (ii) relaxation time.
A conductor of length L is connected to a dc source of emf ε. 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?
A conductor of length L is connected to a dc source of emf ε. 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?
CBSE DELHI - SET 1 2011
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Drift velocity: The average velocity with which the free electrons drift under the influence of an external field. RelaxationTime: Average time interval between two successive collisions of an electron with the ions/atoms of the conductor. The drift velocity will be inversely proportional to 1 $( \text {or }\text{v}_{d}\propto\frac{1}{l})$ and hence it will become one third of its initial value.Alternate Answer
$\text{V}'_{d} = \frac{\text{V}_{d}}{3}.$
$\text{V}'_{d} = \frac{\text{V}_{d}}{3}.$
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