Hi, I am having some trouble with the following question:(adsbygoogle = window.adsbygoogle || []).push({});

You (mass 70.1 kg) decide to take off--literally--with a helium balloon of mass 31.6 kg. The densities of air and helium are air = 1.321 kg/m3 and helium = 0.179 kg/m3. What volume of helium is needed to levitate you and the balloon?

I think that you use the buoyant force equations, but I am not sure how. I tried doing it like this:

F(buoy)=density(fluid)*V'*g or

(101.7*9.81)=(1.321*V'*9.81) and solved for V' and got

V'=76.987 m^3

but this is not correct.

I cannot figure out how to do this problem, any help would be appreciated.

Thanks!!

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# Homework Help: Buoyant force problem

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