[tex]dane:\\q_1 = q_2 = q\\r = 20 \ cm = 0,2 \ m = 2\cdot10^{-1} \ m\\F = 20 \ \mu N = 0,00002 \ N = 2\cdot10^{-5} \ N\\k = 9\cdot10^{9}\frac{N\cdot m^{2}}{C^{2}}\\szukane:\\q = ?\\\\F = k\cdot\frac{q_1\cdot q_2}{r^{2}}\\\\q_1 = q_2 = q, \ wiec\\\\F = k\cdot\frac{q^{2}}{r^{2}} \ \ |\cdot\frac{r^{2}}{k} \\\\q^{2} = \frac{r^{2}\cdot F}{k}\\\\q = \sqrt{\frac{r^{2}\cdot F}{k}}}\\\\q =\sqrt{\frac{(2\cdot10^{-1})^{2}\cdot2\cdot10^{-5}}{9\cdot10^{9}}} \ \ [C][/tex]
[tex]q = \sqrt{\frac{4\cdot10^{-2}\cdot2\cdot10^{-5}}{9\cdot10^{9}}} \ \ [C]\\\\q = \sqrt{0,89\cdot10^{-16}} \ C \\\\q = 94\cdot10^{-8} \ C = 9,4\cdot10^{-9} \ C = 9,4 \ nC[/tex]
Odp. Każdy ładunek ma wartość q = 9,4 nC.
