Using the mathematical expression for the conductivity of a material, explain how it varies with temperature for (i) semiconductors, (ii) good conductors.

Using the mathematical expression for the conductivity of a material,

1.	Using the mathematical expression for the conductivity of a material, explain how it varies with temperature for (i) semiconductors, (ii) good conductors.
Answer» SOLUTION :Conductivity of a material is reciprocal of its RESISTIVITY i.e., `rho = 1/rho` THUS, `sigma = J/E = ("ne"^2 tau)/(m)` . THEREFORE, (i) a semiconductor increases with increase in temperature, but that of (ii) a good conductor decreases with increase in temperature.

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Using the mathematical expression for the conductivity of a material, explain how it varies with temperature for (i) semiconductors, (ii) good conductors.

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