[tex]dane:\\v = 1,5\frac{m}{s}\\F = 400 \ N\\t = 2 \ h = 2\cdot3600 \ s = 7200 \ s\\szukane:\\W = ?\\\\W = F\cdot s\\\\s = v\cdot t = 1,5\frac{m}{s}\cdot7200 \ s = 10 \ 800 \ m\\\\W = 400 \ N\cdot10800 \ m\\\\W = 4 \ 320 \ 000 \ J = 4 \ 320 \ kJ = 4,32 \ MJ\\\\\\1 \ kJ = 1000 \ J\\1 \ MJ = 1 \ 000 \ 000 \ J[/tex]
