Current Electricity Charging Discharging Of Capacitors Question 692
Question: The number of free electrons per 100 mm of ordinary copper wire is $ 2\times 10^{21}. $ Average drift speed of electrons is 0.25 mm/s. The current flowing is
Options:
A) 5 A
B) 80 A
C) 8 A
D) 0.8 A
Show Answer
Answer:
Correct Answer: D
Solution:
[d] $ I=n,e,A,v _{d} $
$ =2\times 10^{21}\times 1.6\times {{10}^{-19}}\times 10\times 0.25\times {{10}^{-3}} $
$ =2\times 1.6\times 0.25=\frac{8}{10}=0.8A $
BETA
