# How many excess protons are in a positively charged object with a charge of +398 mC (millicoulombs)?

Dec 9, 2015

$2.49 \times {10}^{18}$
The charge on 1 proton is $+ 1.6 \times {10}^{- 19} \text{C}$
So the no. of protons that carry $398 \text{mC}$ of charge is:
$\frac{398 \times {10}^{- 3}}{1.6 \times {10}^{- 19}} = 2.49 \times {10}^{18}$