Physics - Current Electricity Question with Solution | TestHub

The drift velocity is given by

$v_d=\frac{I}{ne\text{A}}$

$\Rightarrow I=n\text{A}e{v}_d...(i)$

The given data is

$$\begin{gathered} I=2\text{A} \\ \text{A}=25\times 10^{-6}{m}^2 \\ n=2\times 10^{28} \\ e=1.6\times 10^{-19}\mathrm{C} \end{gathered}$$

Substituting the given values in equation (i)

$$\begin{gathered} 2=2\times 10^{28}\times 25\times 10^{-6}\times 1.6\times 10^{-19}\times v_d \\ \Rightarrow v_d=\frac{2}{2\times 10^{28}\times 25\times 10^{-6}\times 1.6\times 10^{-19}} \end{gathered}$$

$\Rightarrow v_d=\frac{1}{25\times 1.6\times 1000}m{\text{s}}^{-1}=25\times 10^{-6}m{\text{s}}^{-1}$