Q. If the electronic charge is $1.6 \times 10^{- 19}\ $C,$\ $then the number of electrons passing through a section of wire per second, when the wire carries a current of 2 A is
A) $1.25 \times 10^{17}$
B) $1.6 \times 10^{17}$
C) $1.25 \times 10^{19}$
D) $1.6 \times 10^{19}$
Explanation
(c) $i = q/t = ne/t$
or $n = \frac{it}{e} = \frac{2 \times 1}{1.6 \times 10^{- 19}} = 1.25 \times 10^{19}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.