1.
[tex]Dane:\\v_1 = 15\frac{m}{s}\\t = 5 \ s\\v_2 = 25\frac{m}{s}\\Szukane:\\a = ?\\\\Rozwiazanie\\\\a = \frac{\Delta v}{t} = \frac{v_2-v_1}{t}\\\\a = \frac{25\frac{m}{s}-10\frac{m}{s}}{5 \ s} = \frac{15\frac{m}{s}}{5 \ s}\\\\\boxed{a = 3\frac{m}{s^{2}}}[/tex]
2.
[tex]v_{o} = 0\\a = 3\frac{m}{s^{2}}\\v = 60\frac{km}{h} = 60\cdot\frac{1000 \ m}{3600 \ s} = 16,(6)\frac{m}{s}\approx16,67\frac{m}{s}\\Szukane:\\t = ?\\\\Rozwiazanie\\\\a = \frac{\Delta v}{t} \ \ \rightarrow \ \ t = \frac{\Delta v}{a}\\\\\Delta v \approx16,67\frac{m}{s}\\\\t \approx\frac{16,67\frac{m}{s}}{3\frac{m}{s^{2}}}\\\\\boxed{t\approx5,6 \ s}[/tex]
