Current Electricity Charging Discharging Of Capacitors Question 413
Question: 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
[AMU (Med.) 2002]
Options:
A) 0.156 × $ {{10}^{-3}} $ m.s?1
B) 0.156 × $ {{10}^{-2}} $ m.s?1
C) 3.12 × $ {{10}^{-3}} $ m.s?1
D) 3.12 × $ {{10}^{-2}} $ m.s?1
Show Answer
Answer:
Correct Answer: A
Solution:
$ v _{d}=\frac{i}{nAe}= $
$ \frac{8}{8\times 10^{28}\times {{(2\times {{10}^{-3}})}^{2}}\times 1.6\times {{10}^{-19}}} $ = $ 0.156\times {{10}^{-3}}m/sec $ .
BETA
