Drift speed of electrons, when $1.5\, A$ of current flows in a copper wire of cross section $5\, mm^2$, is $v$. If the electron density in copper is $9 \times 10^{28}\, m^3$ the value of $v$ in $mm/s$ is close to (Take charge of electron to be $= 1.6 \times 10^{-19}\, C$)
A$0.02$
B$3$
C$2$
D$0.2$
JEE MAIN 2019, Medium
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A$0.02$
a $\mathrm{i}=\mathrm{ne} \mathrm{AV}_{\mathrm{d}}$
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