Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
A current of $5 \mathrm{~A}$ is passing through a metallic wire of cross-sectional area $4 \times 10^{-6} \mathrm{~m}^{2}$ If the density of charge carriers of the wire is
$5 \times 10^{26} \mathrm{~m}^{-3}$ the drift velocity of the electronswill be
PhysicsCurrent ElectricityKCETKCET 2007
Options:
  • A $1 \times 10^{2} \mathrm{~ms}^{-1}$
  • B $1.56 \times 10^{-2} \mathrm{~ms}^{-1}$
  • C $1.56 \times 10^{-3} \mathrm{~ms}^{-1}$
  • D $1 \times 10^{-2} \mathrm{~ms}^{-1}$
Solution:
1834 Upvotes Verified Answer
The correct answer is: $1.56 \times 10^{-2} \mathrm{~ms}^{-1}$
Drift velocity, $v_{d}=\frac{1}{n e A}$
$$
\begin{aligned}
\Rightarrow v_{d} &=\frac{5}{\left(5 \times 10^{26}\right) \times\left(1.6 \times 10^{-19}\right) \times\left(4 \times 10^{-6}\right)} \\
&=\frac{1}{64}=1.56 \times 10^{-2} \mathrm{~ms}^{-1}
\end{aligned}
$$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.