[tex]dane:\\v_{o} = 0\\h = 5 \ m\\g = 10\frac{m}{s^{2}}\\szukane:\\v = ?\\\\Rozwiazanie\\\\Z \ zasady \ zachowania \ energii\\\\E_{p} = E_{k}\\\\mgh = \frac{mv^{2}}{2} \ /:m\\\\gh = \frac{v^{2}}{2} \ \ /\cdot2\\\\v^{2} = 2gh\\\\v = \sqrt{2gh}\\\\v = \sqrt{2\cdot10\frac{m}{s^{2}}\cdot5 \ m}} = \sqrt{100\frac{m^{2}}{s^{2}}}}\\\\v = 10\frac{m}{s}[/tex]
Odp. Kasztan osiągnie prędkość v = 10 m/s.
