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Homework Help: Simplifying the Buckingham equation

  1. Aug 17, 2011 #1
    Hello, i have a question which is too hard for me to type in here, so ive scanned in the image.
    At the top, as explained in the image, i have the answer ive found in my lecture notes, but then ive worked it out for myself and i do not get the same answer.
    Can someone please tell me where im going wrong?
    Im making V2 the subject

    All help is appretiated, dont be shy.

    heres the link: http://www4.picturepush.com/photo/a/6324532/640/6324532.jpg

    p.s i originally posted this in yahoo answers but got no response.
  2. jcsd
  3. Aug 23, 2011 #2


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    hello stevemilw! :smile:

    i don't understand what you mean by "the apparent answer leaves me with a negative square root and no divider" :confused:

    (and your z1 + z2 should be 2g(z1 + z2))
  4. Aug 23, 2011 #3
    What i meant by that is my answer (at the very bottom) gave me the top part with the pressures devided by the bottom part.
    Also im not sure what you meant by it should be 2G(Z1+Z2) because as i x2g on both sides, shouldnt i only times by one of the sides either side of the plus? writing this now, that seems stupid. You must be right.

    What i mean by the whole thing, is you have the buckingham equation at the very top.
    Second equation is the answer that my textbook says i should get when i re-arrange the formula to make V2 the subject.
    The third equation annd the next and so on are my attempts. And i do not the the answer my text book gives as you can see at the bottom.

  5. Aug 23, 2011 #4


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    they look the same to me :confused:

    (with X-1/2 instead of 1/√X )
  6. Aug 23, 2011 #5
    ooooh, i feel really stupid now.
    I didnt realise that x^-1/2 was 1/sqrt x

    God, you wouldnt believe the amount of hassel thats given me!

    I know -1 was one over, to the negetive half is 1 over the sqrt.

    Thanks, this is something im not going to forget in a while! lol
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