[tex]dane:\\V = 15 \ cm \times 10 \ cm\times 2 \ cm = 300 \ cm3 = 0,0003 \ m^{3}\\d = 1000\frac{kg}{m^{3}}\\g = 10\frac{N}{kg}\\szukane:\\F_{w} = ?\\\\Rozwiazanie\\\\F_{w} = d\cdot g\cdot V\\\\F_{w} = 1000\frac{kg}{m^{3}}\cdot10\frac{N}{kg}\cdot0,0003 \ m^{3}\\\\F_{w} = 3 \ N[/tex]
