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

A helium balloon ride lifts up passengers in a basket. Assume the density of air is 1.28 kg^{1}m^{-3}and the density of helium in the balloon is 0.18 kg^{1}m^{-3}. The radius of the balloon (when filled) is R = 5 m. The total mass of the empty balloon and basket is m_{b}= 123 kg and the total volume is V_{b}= 0.066 m^{3}. Assume the average person that gets into the balloon has a mass m_{p}= 73 kg and volume V_{p}= 0.076 m^{3}. What is the magnitude of the buoyant force on the entire system (but with no people)? Include the volume of the balloon, basket, and helium.

2. Relevant equations

[tex]V_{sph} = \frac{4}{3} \cdot \pi \cdot r^3[/tex]

[tex] F_b = \rho_{fluid} \cdot V \cdot g [/tex]

3. The attempt at a solution

Since the volume of the balloon and basket is given by [tex]V_b[/tex] and the volume of the balloon is given by [tex]\frac{4}{3} \cdot \pi \cdot R^3,[/tex] it seems natural to conclude that the magnitude of the buoyancy force is [tex](1.28 \cdot V_b + 0.18 \cdot \frac{4}{3} \cdot \pi \cdot R^3) \cdot g,[/tex] but this does not seem to provide the correct answer. Any advice?

Thank you for your time. :)

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# Homework Help: A Helium Balloon and Buoyancy

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