Resposta :
Para isto vamos utilizar a fórmula da Lei de Coulomb:
[tex]\vec{F}=k.\frac{q_1.q_2}{d^2} \\ \\ 9.10^{-2}=9.10^9.\frac{q^2}{1^2} \\ \\ q^2=\frac{9.10^{-2}}{9.10^9} \\ \\ q^2=10^{-11} \\ \\ q=(10^{-11}})^{\frac{1}{2}} \\ \\ \boxed{q=10^{\frac{-11}{2}}C} [/tex]
[tex]\vec{F}=k.\frac{q_1.q_2}{d^2} \\ \\ 9.10^{-2}=9.10^9.\frac{q^2}{1^2} \\ \\ q^2=\frac{9.10^{-2}}{9.10^9} \\ \\ q^2=10^{-11} \\ \\ q=(10^{-11}})^{\frac{1}{2}} \\ \\ \boxed{q=10^{\frac{-11}{2}}C} [/tex]