Assuming the expression for drift velocity, derive the expressionfor conductivityof a materialsigma="ne"^2 tau//m.

Assuming the expression for drift velocity, derive the expressionfor c

1.	Assuming the expression for drift velocity, derive the expressionfor conductivityof a materialsigma="ne"^2 tau//m.
Answer» SOLUTION :We KNOW that drift velocity `V_d =(eE tau)/m` We have CURRENT `I="NE" AV_d`…(1) Substitute `V_d` in eqn.(1) `I="ne"A(eEtau)/m =("ne"^2 A E tau)/m` `I/A=("ne"^2 Etau)/m rArr j=("ne"^2 E tau)/m` We know that `j=sigmaE` `therefore sigma cancelE=("ne"^2 cancelE tau)/m` `sigma=("ne"^2 tau)/m`

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Assuming the expression for drift velocity, derive the expressionfor conductivityof a materialsigma="ne"^2 tau//m.

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