Question

Assuming that the charges of an electron is $1.6\times {10}^{-19}coulombs$, the number of electrons passing through a section of wire per sec, when the wire carries a current of one ampere is:

• A. $0.625\times {10}^{19}$
• B. $1.6\times {10}^{-19}$
• C. $1.6\times {10}^{19}$
• D. $0.627\times {10}^{-17}$

Answer 1

The correct option is A $0.625\times {10}^{19}$

We know that current is $i=\frac{Q}{T}$ also time t=1 sec , i=1A

let the total number of electron be n , then $Q=ne$ , e is charge of electron

So $i=1=\frac{ne}{t}=\frac{n\times 1.6\times {10}^{-19}}{1}$

$n=0.625\times {10}^{19}$