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How Does Drift Velocity of Electrons in a Metallic Conductor Vary with Increase in Temperature? Explain.

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Question

How does drift velocity of electrons in a metallic conductor vary with increase in temperature? Explain.

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Solution

Drift velocity of electrons in a metallic conductor decreases with increase in temperature. 

As we know,

As, we increase the temperature of the metallic conductor the collision between the electrons and ions increases, which results in the decrease in the relaxation time.  so, from the equation (4) 

v r

Hence, the drift velocity decreased.

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2015-2016 (March) All India Set 2 C

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