Hi i have this question:(adsbygoogle = window.adsbygoogle || []).push({});

A balloon is filled with helium gas which weighs approximately one-seventh of what air weighs under identical conditions. The balloon has a diameter of 10 m and carries two people, each weighing 70 kg. Assume the density of air is 1.16 kg/m3 and neglect the weight of the ropes and cage. Determine:

(a) The acceleration of the balloon when it is first released

This is how ive been doing it

F= 1.16/7 * 9.81 * 523.6 = 852.7 - Buoyancy equation

Then i got the weight by doing

W= 140 * 9.81 = 1373.4

First of all im not sure if these are right and if they were ive been taking away the buoyancy force from the weight to get 520.7

Then to get accleration i divided it by the mass 140

to get 3.72

But the answer giving said its 16.465

Can anyone please tell me where im going wrong thanks

And weirdly theres a secound question thats says find the maximum load that it can carry and the answer is 520.61 which is very close to my answer

Cheers

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# Homework Help: Buoyancy Balloon

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