S.21 2-6

a)
$A=18{,}4cm\cdot23{,}9cm=439{,}76cm^2=0{,}043976m^2$

$m=330g=0{,}33kg$

$g=9{,}81\frac{m}{s^2}$

$p=\frac{F}{A}=\frac{G}{A}=\frac{mg}{A}=\frac{0{,}33kg\cdot9{,}81\frac{m}{s^2}}{0{,}043976m^2}=73{,}615...\approx74Pa$
V: N. 74Pa.
b)
$p=\frac{F}{A}=101325Pa=\frac{F}{0{,}043976m^2}=101325Pa\cdot0{,}043976m^2=4455{,}8682N\approx4500N=4{,}5kN$
V: N.4,5kN.
c)
Kirjan alhalta tuleva ilmapaine kumoa ylähltä tuleva ilmapainetta