[tex]Dane:\\v_{o} = 0\\h = 30 \ m\\g = 10\frac{m}{s^{2}}\\Szukane:\\v = ?\\\\Rozwiazanie\\\\Z \ zasady \ zachowania \ energii\\\\E_{p} = E_{k}\\\\mgh = \frac{mv^{2}}{2} \ \ /\cdot\frac{2}{m}\\\\v^{2} = 2gh\\\\v = \sqrt{2gh}\\\\v = \sqrt{2\cdot10\frac{m}{s^{2}}\cdot30 \ m}}\\\\v = \sqrt{600\frac{m^{2}}{s^{2}}}\\\\\boxed{v\approx24,49\frac{m}{s}}[/tex]
