[tex]Dane:\\m = 1 \ 200 \ kg\\v_{o} = 0\\W = 240 \ kJ = 240 \ 000 \ J\\Szukane:\\v = ?\\\\Rozwiazanie\\\\W = E_{k} = \frac{mv^{2}}{2}\\\\W = \frac{mv^{2}}{2} \ \ \ |\cdot\frac{2}{m}\\\\v^{2} = \frac{2W}{m}\\\\v = \sqrt{\frac{2W}{m}}\\\\v = \sqrt{\frac{2\cdot240000 \ J}{1200 \ kg}} = \sqrt{\frac{480000 \ kg\cdot\frac{m^{2}}{s^{2}}}{1200 \ kg}}=\sqrt{400\frac{m^{2}}{s^{2}}}\\\\\boxed{v = 20\frac{m}{s}}[/tex]
Odp. Prędkość samochodu v = 20 m/s.
