[tex]dane:\\v_{o} = 0\\a = 5\frac{m}{s^{2}}\\v = 72\frac{km}{h} = 72\cdot\frac{1000 \ m}{3600 \ s} = 20\frac{m}{s}\\szukane:\\t = ?\\\\Rozwiazanie\\\\Dla \ \ v_{o} = 0\\\\v = a\cdot t \ \ /:a\\\\t = \frac{v}{a}\\\\t = \frac{20\frac{m}{s}}{5\frac{m}{s^{2}}}\\\\t = 4 \ s[/tex]
Odp. W czasie 4 sekund.
