1.
[tex]dane:\\m = 3 \ t = 3 \ 000 \ kg\\g = 10\frac{m}{s^{2}}\\h = 10 \ m\\szukane:\\W = ?\\\\Rozwiazanie\\\\W = E_{p}= mgh\\\\W = mgh\\\\W = 3000 \ kg\cdot10\frac{m}{s^{2}}\cdot10 \ m\\\\W = 300 \ 000 \ J = 300 \ kJ[/tex]
2.
[tex]m = 15 \ kg\\E_{p} = 0,45 \ kJ = 450 \ J=450 \ \frac{kg\cdot m^{2}}{s^{2}}\\g = 10\frac{m}{s^{2}}\\h = ?\\\\Rozwiazanie\\\\W = E_{p} = mgh\\\\W = mgh \ \ /:mg\\\\h = \frac{W}{m\cdot g}\\\\h = \frac{450 \ \frac{kg\cdot m^{2}}{s^{2}}}{15 \ kg\cdot10\frac{m}{s^{2}}}}=3 \ m[/tex]
