Current Electricity Charging Discharging Of Capacitors Question 693
Question: At room temperature, copper has free electron density of $ 8.4\times 10^{28} $ per $ m^{3}. $ The copper conductor has a cross-section of $ {{10}^{-6}}m $ and velocity in copper is
Options:
A) $ 36{}^\circ C $
B) $ 83{}^\circ C $
C) $ 63{}^\circ C $
D) $ 33{}^\circ C $
Show Answer
Answer:
Correct Answer: C
Solution:
[c] $ v _{d}=\frac{1}{neA} $ here, $ I=5.4A,n=8.4\times 10^{28}, $
$ \text{per }{{\text{m}}^{\text{3}}} $
$ \text{A=1}{{\text{0}}^{-6}}m^{2},e=1.6\times {{10}^{-19}}C $
$ \
Therefore v _{d}=\frac{5.4}{8\times 10^{28}\times 1.6\times {{10}^{-19}}\times {{10}^{-6}}}=0.4mm/s $
BETA
