(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

How many cubic meters of helium are required to lift a balloon with 400kg payload to a height of 8000m where the density of air is 0.460kg/m^3 and the density of helium is 0.180kg/m^3. Assume that the balloon maintains a constant volume.

2. Relevant equations

[tex]\rho = M/V[/tex]

[tex]F=PA[/tex]

[tex]F=\rho*g*V[/tex]

[tex]P=\rho * g * h[/tex]

3. The attempt at a solution

Firstly i found the volume of air which is 869.59m^3 and then from this i found the Buoyancy force for air. The Buoyancy force for air is 3920.02156N

Now to find the Volume of helium

[tex]F=\rho*g*V[/tex]

[tex]3920.02156 = 0.180 * 9.8 * V[/tex]

[tex]V =2222.234m^3[/tex]

However this is the wrong answer, someone tell me what is the problem with my solution?

P.S

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