Need to see if I worked this right.(adsbygoogle = window.adsbygoogle || []).push({});

Hot air balloon floating in air has at 0 degrees C ( desnsity = 1.293kg/m^3). The mass of the balloon and passengers is 1650kg. If they want to stay at a constant height, estimate the required average temperature of the air in the balloon. Assume the volume of air in the balloon is 5000m^3 and the density of air varies with temperature according to the following information.

-10 degrees C = 1.341 kg/m^3

-5 degrees C = 1.316 kg/m^3

0 degrees C = 1.293 kg/m^3

+5 degrees C = 1.269 kg/m^3

+10 degrees C = 1.247 kg/m^3

MY SOLUTION:

B = (1.293kg/m^3)(5000m^3)(9.81m/s^2) = 63422N Buoyant Force

Weight of Balloon is (1650kg)(9.81m/s^2) = 16187N

63422N-16187N=47235N

47235N/9.81m/s^2 = 4815kg

Density of air in balloon is 4185kg/5000m^3 = .963kg/m^3

So here I would have to assume the Pressure is standard and is equal to 101325 so from row=P/RT it would give me a temp in degrees C of 93.5. I assume that pressure because it seems that was the value he used in the table to calculate the density for the temps from -10 to +10.

Have I made any mistakes? Thanks

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# Homework Help: Please check this problem

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