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Problem: What is the mean free time between collisions for electrons in an iron wire and an aluminum wire?

FREE Expert Solution

The mean free time between collisions for electrons ina wire is expressed as:

$\overline{){\mathbf{\tau }}{\mathbf{=}}\frac{\mathbf{m}\mathbf{\sigma }}{{\mathbf{n}}_{\mathbf{e}}{\mathbf{e}}^{\mathbf{2}}}}$

For electrons in an iron wire:

$\begin{array}{rcl}\mathbf{\tau }& \mathbf{=}& \frac{\mathbf{\left(}\mathbf{9}\mathbf{.}\mathbf{11}\mathbf{×}{\mathbf{10}}^{\mathbf{-}\mathbf{31}}\mathbf{\right)}\mathbf{\left(}\mathbf{1}\mathbf{×}{\mathbf{10}}^{\mathbf{7}}\mathbf{\right)}}{\mathbf{\left(}\mathbf{8}\mathbf{.}\mathbf{5}\mathbf{×}{\mathbf{10}}^{\mathbf{28}}\mathbf{\right)}\mathbf{\left[}{\mathbf{\left(}\mathbf{1}\mathbf{.}\mathbf{6}\mathbf{×}\mathbf{10}\mathbf{-}\mathbf{19}\mathbf{\right)}}^{\mathbf{2}}\mathbf{\right]}}\end{array}$

Problem Details
What is the mean free time between collisions for electrons in an iron wire and an aluminum wire?