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i Had a question put to me that i am not positive of the answer.

i have a air reciever that is holding 100 cu.ft. of air at 50 psig then a compressor pumps in 1500 cu.ft. of air . What is the final pressure?

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I know you've stated that you're not positive of the answer but, tell me what your best guess is and how did you arrive at that answer.

Just curious.
U-Guy
SkunkWorks
to find how many cu ft of free air it took to get the pressure up to 50 psi 14.7 X V1 = (50+14.7) X 100 this = 440.14 cu.ft.so now we put the extra 1500 added to this 14.7 X (1500+440.14) = P2 X 100 this = 285.2 psia - 14.7=270.5psi

this is how i figured it out but have had colleagues say thats the wrong way

What do you think?
Since you posted this inquiry about six months ago I figured you most likely had already found the answer you were looking for.

I googled up some pages that were set up to help make these "boyles law" calculations. Oddly enough, my guesses -with the help of these "calculators"- were similar to what you've just posted. NOT!

Because I absolutely suck at anything concerning mathematical calculations, I automatically assumed my answers were anything but correct.

I divided 100 into 1550 and then multiplied it by 14.7 = 227.85.

My reason for asking to see your answer was strictly out curiosity. I really did try to find the answer; mainly because I'm working on a project that "boyles law" actually applies to. Since I suck at mathematical equations and such, I'm stuck with the trial and error method of coming up with answers.

Can you tell me the answers your colleagues came up with and how they arrived at these answers? I think that with the initial numbers you posted and the correct answers your colleagues came up with there is a chance I can sort of reverse-engineer the answers (if that makes any sense) and possibly be able to come closer to getting correct answers to my own mathematical questions.

Thanks
U-Guy
SkunkWorks