Answer:
[tex]6.19\times10^{-8}[/tex] C
Explanation:
In order to cause a breakdown and a spark the electric field should be at least
E = [tex]3.3\times10^{6} N/C[/tex]
We know that
a free electron in air is r = 1.3 cm away from a point charge.
[tex]E=k \frac{q}{r^2}[/tex]
[tex]k= \frac{1}{4\pi\epsilon_o}[/tex]
therefore,
[tex]q= \frac{r^2E}{k}[/tex]
substituting the values we get
[tex]q= \frac{(1.3\times10^{-2})^2(3.3\times10^6)}{9\times10^9}[/tex]
= [tex]6.19\times10^{-8}[/tex] C