1st October 2009 - 08:08 AM
3. A 10 ft^3 tank contains gas at a pressure of 500 psia, temperature of 85 Fahrenheit and a weight of 25 lbs. A part of the gas was discharged and the temperature and pressure changed to 70 fahrenheit and 300 psia, respectively. Heat was applied and the temperature was back to 85 fahrenheit. Find the final weight, volume, and pressure of the gas.
how it arrive to this answer? please show a solution
Answer : 15.43 lb; 10 ft^3; 308.5 psia
1st October 2009 - 05:44 PM
Why should we if you don't show us how you try first?
1st October 2009 - 10:40 PM
Convert your Fahrenheit temperatures into degrees Kelvin [Moderator: Somewhat easier, and just as effective, if more obscure, degrees Rankine -- see the earlier post. http://www.physforum.com/index.php?showtopic=26658
].. if you can do that then anyone (even me, probably even you) can answer the question.
1st October 2009 - 11:07 PM
So this setup is the same as before:
P₁V₁/N₁T₁ = P₂V₁/N₂T₂ = P₃V₁/N₂T₃
So N₂ = (T₁/T₂)(P₂/P₁)N₁
And P₃ = (N₂/N₁)(T₃/T₁)P₁ = (T₃/T₂)P₂
Oh, and the weight of the gas is proportional to N.
Oh, and for this problem, T₃ =T₁.
Finally, your book has some odd convention with respect to rounding.
3rd October 2009 - 05:03 AM
Thanks for giving me some insight about this, sorry because i am trying but I can't get the correct answer. The book has answer but no slution thats why I included the answer...Thanks again and more power...