Drift velocity V_d varies with the intensity | vedclass

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(A) The current $I$ in a conductor is given by $I = n e A v_d$,where $n$ is the number density of electrons,$e$ is the charge of an electron,$A$ is th

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$V_d \propto E$

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(A) The current $I$ in a conductor is given by $I = n e A v_d$,where $n$ is the number density of electrons,$e$ is the charge of an electron,$A$ is the cross-sectional area,and $v_d$ is the drift velocity.The current density $J$ is defined as $J = \frac{I}{A} = n e v_d$.According to Ohm's law in microscopic form,the current density $J$ is related to the electric field $E$ by the relation $J = \sigma E$,where $\sigma$ is the electrical conductivity.Equating the two expressions for $J$,we get $n e v_d = \sigma E$.Since $n$,$e$,and $\sigma$ are constants for a given material at a constant temperature,it follows that $v_d \propto E$.

Drift velocity $V_d$ varies with the intensity of electric field $E$ as per the relation:

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