Hi I really need help figuring out this problem. A balloon behaves such that the pressure inside is proportional to the diameter squared. It contains 2 Kg of ammonia at 0 degrees celcius and 60% quality. The balloon and ammonia are now heated so that a final pressure of 600 kPa is reached. Considering the ammonia as a control mass, find the amout of work done in the process.(adsbygoogle = window.adsbygoogle || []).push({});

the answer is 117.19 KJ

i was able to find the initial volume from the quality and mass

I got Vinitial = 0.3483

I cant find a way to get a value for n in the polytropic process equation

W = (P2V2-P1V1)/ 1-n

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# Homework Help: Polytropic process where n is not given

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