(A) The formula for drift velocity is given by $v_d = \frac{I}{nAe}$.Here,$I = 8 \, A$,$n = 8 \times 10^{28} \, m^{-3}$,and $e = 1.6 \times 10^{-19} \

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(A) The formula for drift velocity is given by $v_d = \frac{I}{nAe}$.Here,$I = 8 \, A$,$n = 8 \times 10^{28} \, m^{-3}$,and $e = 1.6 \times 10^{-19} \, C$.The cross-sectional area $A$ of the square wire is $(2.0 \, mm)^2 = (2.0 \times 10^{-3} \, m)^2 = 4 \times 10^{-6} \, m^2$.Substituting these values into the formula:$v_d = \frac{8}{8 \times 10^{28} \times 4 \times 10^{-6} \times 1.6 \times 10^{-19}}$$v_d = \frac{8}{51.2 \times 10^3} = \frac{1}{6.4} \times 10^{-3} \approx 0.156 \times 10^{-3} \, m/s$.

Class 12 Physics Current Electricity Current Density, Drift Velocity and Mobility

Easy

$A$ copper wire has a square cross-section,$2.0 \, mm$ on a side. It carries a current of $8 \, A$ and the density of free electrons is $8 \times 10^{28} \, m^{-3}$. The drift speed of electrons is equal to

A
$0.156 \times 10^{-3} \, m/s$
B
$0.156 \times 10^{-2} \, m/s$
C
$3.12 \times 10^{-3} \, m/s$
D
$3.12 \times 10^{-2} \, m/s$

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Current Electricity

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Current Density, Drift Velocity and Mobility

$A$ current of $2 \,A$ is passing through a metal wire of cross-sectional area $2 \times 10^{-6} \,m^{2}$. If the number density of free electrons in the wire is $5 \times 10^{26} \,m^{-3}$, the drift speed of electrons is (Given, $e = 1.6 \times 10^{-19} \,C$)

MediumKCET 2012

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$A$ wire has a non-uniform cross-section as shown in the figure. $A$ steady current flows through it. The drift speed of electrons at points $P$ and $Q$ is $v_P$ and $v_Q$ respectively.

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$A$ cylindrical conductor of diameter $0.1 \text{ mm}$ carries a current of $90 \text{ mA}$. The current density (in $\text{Am}^{-2}$) is (take $\pi \simeq 3$):

DifficultKCET 2017

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The area of cross-section of a copper wire is $4 \times 10^{-7} \,m^2$ and the number of free electrons per cubic metre in copper is $8 \times 10^{28}$. If the wire carries a current of $6.4 \,A$,then the drift velocity of the electrons (in $10^{-3} \,m \,s^{-1}$) is:

MediumAP EAMCET 2025

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Consider a wire carrying a current of $10\,A$ with a cross-sectional area of $1\,cm^2$. If the number of electrons per unit volume is $9 \times 10^{28}\,m^{-3}$,find the drift velocity of the electrons.

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$A$ copper wire has a square cross-section,$2.0 \, mm$ on a side. It carries a current of $8 \, A$ and the density of free electrons is $8 \times 10^{28} \, m^{-3}$. The drift speed of electrons is equal to

Similar Questions

$A$ current of $2 \,A$ is passing through a metal wire of cross-sectional area $2 \times 10^{-6} \,m^{2}$. If the number density of free electrons in the wire is $5 \times 10^{26} \,m^{-3}$, the drift speed of electrons is (Given, $e = 1.6 \times 10^{-19} \,C$)

$A$ wire has a non-uniform cross-section as shown in the figure. $A$ steady current flows through it. The drift speed of electrons at points $P$ and $Q$ is $v_P$ and $v_Q$ respectively.

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