Electron density in a copper wire is `8.0 xx10^(22) cm ^(-3)`. Calculate the relaxation time for electrons if the resistivity of copper is `1.68xx10^(-8) Omega m` at room temperature.
(Massof electron is `9.1 xx10^(-31) kg`.)

Explanation

To calculate the relaxation time (τ) for electrons in a copper wire, we can use the relationship between resistivity (ρ), electron density (η), mass of the electron (m), and the charge of the electron (e). The formula we will use is:

\[ \rho = \frac{m}{\eta e^2 \tau} \]

From this formula, we can rearrange it to solve for τ:

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