How do I figure this out?
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  1. #1

    Confused How do I figure this out?

    A cylinder with 1,500 sq. in. of internal surface contains R-22 and is in a service truck body at 120F. What is the total outward force of the refrigerant against the inner wall of the cylinder in tons of pressure?

    A. 202.64
    B. 226.61
    C. 194.92
    D. 145.71

    Can someone give me the equation to figuring this one out?

  2. #2
    Join Date
    Apr 2008
    Location
    Southern New Hampshire (USA)
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    401
    It's C

    R-22@120*=260 PSI (pounds per square inch)
    you have 1500 sq in, so

    260 x 1500 = 390000 pounds
    1 ton=2000 pounds

    390000/2000= 195

  3. #3
    Thanks Nightranger!!

  4. #4
    Join Date
    Apr 2008
    Location
    Southern New Hampshire (USA)
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    401
    No prob

  5. #5
    Join Date
    Apr 2008
    Location
    Southern New Hampshire (USA)
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    401
    That question was really tricky, though and I'd love to know the real-world practical application for that. Or is it just meant to scare you from getting your tanks too hot?

  6. #6
    Join Date
    May 2008
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    TDOT
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    nice thinking nightranger but R-22 @120* is 260 PSIG which is equivalent to 274.696 PSI (pounds per square inch)

  7. #7
    Join Date
    Jan 2004
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    Lancaster PA
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    67,611
    Thats 260PSIG, or 274.696 PSIA.
    Since A would be low if using PSIA, I think C is the answer they were looking for.
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  8. #8
    Join Date
    May 2008
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    TDOT
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    ya just sayin he forgot to say it was PSIG and not PSI because if he writes that on some homework he may loose some marks if the PROF is in a bad mood, witnessed it happen to often

  9. #9
    Join Date
    Jan 2004
    Location
    Lancaster PA
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    Quote Originally Posted by Matt- View Post
    ya just sayin he forgot to say it was PSIG and not PSI because if he writes that on some homework he may loose some marks if the PROF is in a bad mood, witnessed it happen to often
    True. But you didn't explain that in your first post.
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