[tex]dane:\\H = 5 \ m\\g = 10\frac{m}{s^{2}}\\szukane:\\v_{o} = ?\\\\Rozwiazanie\\\\E_{p} = E_{k}\\\\mgH = \frac{mv_{o}^{2}}{2} \ \ /\cdot\frac{2}{m}\\\\v_{o}^{2} = 2gH\\\\v_{o} = \sqrt{2gH}\\\\v_{o} = \sqrt{2\cdot10\frac{m}{s^{2}}\cdot5 \ m} = \sqrt{100\frac{m^{2}}{s^{2}}}\\\\v_{o} = 10\frac{m}{s}[/tex]