Question
How resistivity of material depends on its temperature. Write its empirical formula.
✓
Answer
$\rightarrow $ The resistivity of a material depends on temperature. Different materials do not exhibit the same dependence on temperature.
$\rightarrow $ Over a limited range of temperatures $($not too large$),$ the resistivity of a metallic conductor is given by,
$\rightarrow \rho_{ T }= \rho _0\left[1+\alpha\left( T - T _0\right)\right]$
where,
$\rho _{ T }=\text { the resistivity at temp. } T$
$\rho _0=\text { the resistivity at reference temp. }$
$\alpha=\text { temperature co-efficient of resistivity }$
$ \text { (unit }{ }^{\circ} C ^{-1} \text { or } K ^{-1} \text { ) }$
$T =\text { given temperature }$
$T _0=\text { reference temperature }$
$\rightarrow $ Over a limited range of temperatures $($not too large$),$ the resistivity of a metallic conductor is given by,
$\rightarrow \rho_{ T }= \rho _0\left[1+\alpha\left( T - T _0\right)\right]$
where,
$\rho _{ T }=\text { the resistivity at temp. } T$
$\rho _0=\text { the resistivity at reference temp. }$
$\alpha=\text { temperature co-efficient of resistivity }$
$ \text { (unit }{ }^{\circ} C ^{-1} \text { or } K ^{-1} \text { ) }$
$T =\text { given temperature }$
$T _0=\text { reference temperature }$
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