A body has a charge of −10 C on it. The number of excess electrons on the body is:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 6.25 × 1019
Charge is quantised: any charge is an integral multiple of the electronic charge, q = ne with \( e = 1.6\times10^{-19}\,\mathrm{C} \). A negative charge means the body has more electrons than protons.
\( \displaystyle n = \frac{|q|}{e} = \frac{10\,\mathrm{C}}{1.6\times10^{-19}\,\mathrm{C}} \)
\( n = 6.25\times10^{19} \)