1.
[tex]dane:\\m = 12\cdot 9 \ kg = 108 \ kg\\S = 1,5 \ m^{2}\\g = 10\frac{N}{kg}\\szukane:\\p = ?\\\\Rozwiazanie\\\\p = \frac{F}{S}\\\\p = \frac{m\cdot g}{S}\\\\p = \frac{108 \ kg\cdot10\frac{N}{kg}}{1,5 \ m^{2}}\\\\p = 720 \ Pa[/tex]
2.
[tex]dane:\\h = 10\cdot 9 \ cm = 90 \ cm = 0,9 \ m\\d = 1,26\frac{g}{cm^{3}} = 1260\frac{kg}{m^{3}}\\g = 10\frac{N}{kg}}\\szukane:\\p = ?\\\\Rozwiazanie\\\\p = d\cdot g\cdot h\\\\p = 1260\frac{kg}{m^{3}}\cdot10\frac{N}{kg}\cdot0,9 \ m\\\\p = 11 \ 340 \ Pa = 11,34 \ kPa[/tex]
3.
[tex]dane:\\S_1 = 4\cdot9 \ cm^{2} = 36 \ cm^{2}\\F_2 = 8F_1\\szukane:\\S_2 = ?\\\\Rozwiazanie\\\\\frac{F_1}{S_1} = \frac{F_2}{S_2}\\\\\frac{S_2}{S_1} = \frac{F_2}{F_1}\\\\\frac{S_2}{S_1} = 8\\\\S_2 = 8S_1\\\\S_2 = 8\cdot36 \ cm^{2}\\\\S_2 = 288 \ cm^{2}[/tex]
3.
[tex]dane:\\V = 0,1\cdot9 \ m^{3} = 0,9 \ m^{3}\\V_{z} = \frac{1}{2}V = \frac{1}{2}\cdot0,9 \ m^{3} = 0,45 \ m^{3}\\d = 810\frac{kg}{m^{3}}\\g = 10\frac{N}{kg}\\szukane:\\F_{w} = ?\\\\Rozwiazanie\\\\F_{w} = d\cdot g\cdot V_{z}\\\\F_{w} = 810\frac{kg}{m^{3}}\cdot10\frac{N}{kg}\cdot0,45 \ m^{3}\\\\F_{w} = 3 \ 645 \ N = 3,645 \ kN[/tex]
