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

  • A
    $8 \times 10^{28} \ m^{-3}$
  • B
    $6 \times 10^{28} \ m^{-3}$
  • C
    $4 \times 10^{28} \ m^{-3}$
  • D
    $5 \times 10^{28} \ m^{-3}$

Explore More

Similar Questions

$A$ potential difference $V$ is applied across the ends of a copper wire of diameter $d$ and length $L$. If only the diameter $d$ is doubled,the drift velocity becomes:

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

In a conductor,if the number of conduction electrons per unit volume is $8.5 \times 10^{28} \ m^{-3}$ and the mean free time is $25 \ fs$ (femtosecond),what is its approximate resistivity? (Given: $m_e = 9.1 \times 10^{-31} \ kg$,$e = 1.6 \times 10^{-19} \ C$)

In a metallic conductor,under the effect of an applied electric field,the free electrons of the conductor

Explain the mobility of a charge carrier in a conductor and derive its equation.

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo