The 4000 m3 balloon is filled with helium. The weight of its structure together with equipment and crew is 30 kN.

The 4000 m3 balloon is filled with helium. The weight of its structure together with equipment and crew is 30 kN. Helium completely fills the cylinders at a height where the air density is 1.2 kg / m3. How much weight can a balloon lift?

P = 30kN – weight of equipment and crew
The strength of Archimedes is determined from
Fa = ro * g * V,
where ro = 1.2kg / m ^ 3 – air density,
g = 10m / s ^ 2 – acceleration of gravity,
V = 4000 m ^ 3 – the volume of the balloon.
Fa = 4000 * 10 * 1.2 = 48000 N = 48 kN
F = Fa – P = 18 kN = 18000 N