A lighter-than-air balloon and its load of passengers and ballast are floating stationary above the earth. Ballast is weight (of negligible volume) that can be dropped overboard to make the balloon rise. The radius of this balloon is 6.25 m. Assuming a constant value of 1.29 kg/m3 for the density of air, determine how much weight must be dropped overboard to make the balloon rise 105 m in 15.0 s.(adsbygoogle = window.adsbygoogle || []).push({});

Hello. The question is above :). Im not quite sure how to do this one, its one of the challenge problems . I think you have to calculate the final velocity (vf^2 = 2g*105m), and compare densities (before vs after). But i dont know how to go about it :(

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# Balloons and pressure Kinda stuck

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