Question

A current of 5 amperes is passing through a metallic wire of cross-sectional area $4\times {10}^{-6}$ m2. If the density of the charge carrier in the wire is $5\times {10}^{26}$ /m3, the drift velocity of the electrons is :

• A. $\frac{1}{8}m/s$
• B. $\frac{1}{16}m/s$
• C. $\frac{1}{64}m/s$
• D. $\frac{1}{78}m/s$

Answer 1

Answer: (C), (D)

The correct options are
C $\frac{1}{64}m/s$
D $\frac{1}{78}m/s$

Using the relation $[V_d=I/(n\times A\times e\left)\right]$ we have,
$[V_d=4/(5\times {10}^{26}\times 1.6\times {10}^{-19}\times 4\times {10}^{-6}\left)\right]$
$[V_d=1/64]$ meter per sec