Question

if there is 10^15 electrons flowing across any cross-section of a conductor in 1 minute, what is the current in the wire? (magnitude of charge of one electron=1.6×10^-19C)

Answer 1

Given, No. Of electrons = 10^15
&, Charge of 1 electron =1.6 × 10^-19 coulomb
Therefore, Charge of 10^15 electrons = 10^15 × 1.6 ×10^-19 C
=1.6 × 10^-4 C

Also Given, Time = 1 min
= 60 sec (In SI unit of time)

We know that, Current is the rate of flow of Charge. So,

Current=Charge/Time
=1.6 × 10^-4 C / 60 sec
=1.6 × 10^-5 C / 6 sec
=0.2667 × 10^-5 C / sec ( 0.2666... is rouned off )
=2.67 × 10^-5 A
(Since, C/sec = ampere)