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Question
Plot a graph showing the variation of resistivity of a conductor with temperature.
Solution
The resistivity of a metallic conductor is given by
\[\rho = \rho_0 \left[ 1 + \alpha\left( T - T_0 \right) \right]\]
\\text { [where }\]
\[ \rho_0 = \text { Resistivity at reference temperature }\]
\[ T_0 =\text { Reference temperature }\]
\[ \alpha = \text { Coefficient of resistivity }\]
From the above relation, we can say that the graph between resistivity of a conductor with temperature is a straight line. But, at temperatures much lower than 273 K ( i.e. \[0 °C\], the graph deviates considerably from a straight line as shown below.
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