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(B) The electric current $I$ in a conductor is given by the relation $I = nAev_d$, where $n$ is the number density of free electrons, $A$ is the cross

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The number density of free electrons is very high and this can compensate for the low values of the electron drift speed and the very small magnitude of the electron charge

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(B) The electric current $I$ in a conductor is given by the relation $I = nAev_d$, where $n$ is the number density of free electrons, $A$ is the cross-sectional area, $e$ is the magnitude of the electron charge, and $v_d$ is the drift speed.Although the drift speed $v_d$ is very small (typically $10^{-4} \, m/s$) and the charge $e$ is also very small $(1.6 	imes 10^{-19} \, C)$, the number density $n$ of free electrons in a conductor is extremely high (typically $10^{28} \, to \, 10^{29} \, m^{-3}$).This very high value of $n$ compensates for the small values of $v_d$ and $e$, allowing for the flow of a significant amount of current through the conductor.

We are able to obtain fairly large currents in a conductor because

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