Two positive charges separated by a distance 2 m each other with a force of 0.36 N. If the combined charge is 26 $\mathrm{\mu }$ C, the charges are

$$\begin{gathered} {\mathrm{Q}}_1+{\mathrm{Q}}_2=26\mathrm{\mu c} ----\left(1\right) \\ \Rightarrow 0.36=9 \mathrm{x} {10}^9 \mathrm{x} \frac{{\mathrm{q}}_1{\mathrm{q}}_2}{2^2} \\ \frac{36 \mathrm{x} {10}^{-2}=9 \mathrm{x} {10}^9 \mathrm{x} \mathrm{q}(26-\mathrm{q}) \mathrm{x} {10}^{-12}}{4} \end{gathered}$$

q (26-q) = 16×10 ; q2 – 26q +160 =0

(q-16) (q-10) = 0 ; Q=16 $\mathrm{\mu }$ C (or) 10 $\mathrm{\mu }$ C