$A$ conductor wire having $10^{29}$ free electrons $/ m^{3}$ carries a current of $20 \,A$. If the cross-section of the wire is $1 \,mm^{2}$, then the drift velocity of electrons will be. $\left(e=1.6 \times 10^{-19} \,C\right)$

An electron takes $40 \times 10^3 \ s$ to drift from one end of a metal wire of length $2 \ m$ to its other end. The area of cross-section of the wire is $4 \ mm^2$ and it is carrying a current of $1.6 \ A$. The number density of free electrons in the metal wire is

Which of the following is the unit of mobility of an electron in a conductor?

$A$ current of $5\; A$ is passing through a non-linear magnesium wire of cross-section $0.04\; m^2$. At every point,the direction of current density is at an angle of $60^{\circ}$ with the unit vector of the area of cross-section. The magnitude of the electric field at every point of the conductor is .... $V/m$ (Resistivity of magnesium is $\rho = 44 \times 10^{-8}\, \Omega m$).

$A$ current of $1.6\, A$ is flowing through a wire having a cross-sectional area of $1\, mm^2$. If the density of free electrons in the material of the wire is $10^{29}\, m^{-3}$,the drift velocity of the electrons will be:

$A$ potential difference $V$ is applied across the ends of a metallic wire of length $l$. The drift velocity will be doubled if: