Question

When a glass rod rubbed with silk cloth acquires a charge of the order of $1\mu C$ then the number of elementary charges on glass rod is given by:

• A. $1.6\times {10}^{+12}$
• B. $6.25\times {10}^{12}$
• C. 20
• D. ${10}^6$

Answer 1

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

$q=1\mu C$
$n=\frac{q}{e}=\frac{1{-}^{-6}C}{1.6\times {10}^{-19}C}$
$=6\cdot 25\times {10}^{12}$