5. d)
6.
[tex]v_1 = 10\frac{m}{s}\\v_2 = 108\frac{km}{h} = 108\cdot\frac{1000 \ m}{3600 \ s} = 30\frac{m}{s}\\\\30\frac{m}{s} > 10\frac{m}{s}\\\\\underline{v_2 > v_1}\\\\\frac{v_2}{v_1} = \frac{30\frac{m}{s}}{10\frac{m}{s}} = 3\\\\\underline{v_2 = 3v_1}[/tex]
7.
[tex]Dane:\\v = 5\frac{m}{s}\\t = 2 \ s\\Szukane:\\l = s = ?\\\\s = v\cdot t\\\\s = 5\frac{m}{s}\cdot2 \ s\\\\\underline{s = 10 \ m}[/tex]
Odp. Długość mostu s = 10 m.
