Question

How many electrons make up a charge of $20\mu C$

• A. $1.25\times 10^{14}$
• B. $2.23\times 10^{14}$
• C. $3.25\times 10^{14}$
• D. $5.25\times 10^{14}$

Answer 1

Answer: (A)

Charge on an electron $=1.6\times 10^{-19}$ coulomb
No. of electrons required $=\frac{20\times 10^{-6}}{1.6\times 10^{-19}}$
$=\frac{20}{1.6}\times 10^{13}=1.25\times 10^{14}$