[tex]dane:\\v_{o} = 0\\v = 20\frac{m}{s}\\g = 10\frac{m}{s^{2}}\\szukane:\\h = ?\\\\E_{p} = E_{k}\\\\mgh = \frac{mv^{2}}{2} \ \ /\cdot\frac{2}{m}\\\\2gh = v^{2} \ \ /:(2g)\\\\h = \frac{h^{2}}{2g}\\\\h = \frac{(20\frac{m}{s})^{2}}{2\cdot10\frac{m}{s^{2}}} = \frac{400\frac{m^{2}}{s^{2}}}{20\frac{m}{s^{2}}} = 20 \ m[/tex]
Odp. Piłka spadła z wysokości h = 20 m.
