[tex]dane:\\v_{o} = 72\frac{km}{h} = 72\cdot\frac{1000 \ m}{3600 \ s} = 20\frac{m}{s}\\t = 5 \ s\\v = 0\frac{m}{s}\\szukane:\\a = ?\\\\Rozwiazanie\\\\a = \frac{\Delta v}{t} = \frac{v_{o}-v}{t} = \frac{v_{o}}{t}\\\\a = \frac{20\frac{m}{s}}{5 \ s} = 4\frac{m}{s^{2}} \ - \ opoznienie[/tex]