Question

How many electrons constitute current of one micro ampere in one second?

• A. $6.25\times {10}^8$
• B. $6.25\times {10}^{12}$
• C. $6.25\times {10}^9$
• D. $6.25\times {10}^{15}$

Answer 1

The correct option is B $6.25\times {10}^{12}$

Given: Current ,$I=1\mu A={10}^{-6}A$
We know that $Q=ne,t=1s$
Where $n$ is the number of electrons and e is the charge on $1$ electron and $e=1.6\times {10}^{-19}C$
$n=\frac{I}{e}=\frac{{10}^{-6}}{1.6\times {10}^{-19}}=6.25\times {10}^{12}Electrons$