Answer:
[tex]0.286 mN/m^2[/tex]
Explanation:
Using Laplace's law of surface tension:
[tex]P=\frac{2T}{r}[/tex]
where:
P = pressure
T = surface tension
r = radius
In the longer alveoli with radius of 0.07 mm = [tex]0.07*10^{-2}m[/tex]; we have:
P = [tex]\frac{2*25mN/m}{0.07*10^{-2}m}[/tex]
P = [tex]0.714 mN/m^2[/tex]
In the smaller alveoli with radius 0.05 mm = [tex]0.05 * 10^{-2} m[/tex]; we have:
P = [tex]\frac{2*25mN/m}{0.05*10^-2m}[/tex]
P = [tex]1.00 mN/m^2[/tex]
The pressure difference can now be calculate as follows:
Pressure difference = [tex](1.00 - 0.714)mN/m^2[/tex]
Pressure difference = [tex]0.286 mN/m^2[/tex]
