Question.
A certain particle carries $2.5 \times 10^{-16} \mathrm{C}$ of static electric charge. Calculate the number of electrons present in it.
A certain particle carries $2.5 \times 10^{-16} \mathrm{C}$ of static electric charge. Calculate the number of electrons present in it.
Solution:
Charge on one electron $=1.6022 \times 10^{-19} \mathrm{C}$
$\Rightarrow 1.6022 \times 10^{-19} \mathrm{C}$ charge is carried by 1 electron.
$\therefore$ Number of electrons carrying a charge of $2.5 \times 10^{-16} \mathrm{C}$
$=\frac{1}{1.6022 \times 10^{-19} \mathrm{C}}\left(2.5 \times 10^{-16} \mathrm{C}\right)$
$=1.560 \times 10^{3} \mathrm{C}$
$=1560 \mathrm{C}$
Charge on one electron $=1.6022 \times 10^{-19} \mathrm{C}$
$\Rightarrow 1.6022 \times 10^{-19} \mathrm{C}$ charge is carried by 1 electron.
$\therefore$ Number of electrons carrying a charge of $2.5 \times 10^{-16} \mathrm{C}$
$=\frac{1}{1.6022 \times 10^{-19} \mathrm{C}}\left(2.5 \times 10^{-16} \mathrm{C}\right)$
$=1.560 \times 10^{3} \mathrm{C}$
$=1560 \mathrm{C}$