OK, I have been working on this for a while.(adsbygoogle = window.adsbygoogle || []).push({});

I have a balloon, filled with helium.

mass = 140 kg

density(air) = 1.16 kg/m^3

density(He) = 1/7*density(air)

diameter of balloon = 10 m

bouyant force = density(air)*g*Volume(balloon)

weight = m*g

net force = bouyant force - weight = ma

I need to solve for a. The book tells the answer (16.5 m/s^2), so I know what I need to get to, but doing the steps above, I haven't gotten close.

Anybody have any ideas to help out?

Thanks!

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# Homework Help: Thermodynamics Question

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