Simplifying the Buckingham equation

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The discussion revolves around a user's confusion in rearranging the Buckingham equation to solve for V2. They initially found a discrepancy between their calculations and the textbook answer. Clarifications were sought regarding the proper manipulation of the equation, particularly about handling terms like 2g(z1 + z2). The user realized a misunderstanding regarding the notation, specifically that x^-1/2 equates to 1/sqrt(x). This exchange highlights the importance of careful attention to mathematical notation and its implications in problem-solving.
stevemilw
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Hello, i have a question which is too hard for me to type in here, so I've scanned in the image.
At the top, as explained in the image, i have the answer I've found in my lecture notes, but then I've worked it out for myself and i do not get the same answer.
Can someone please tell me where I am going wrong?
Im making V2 the subject

All help is appretiated, don't be shy.
Thanks!

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.
 
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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))
 
Hello
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 I am not sure what you meant by it should be 2G(Z1+Z2) because as i x2g on both sides, shouldn't 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 textbook gives as you can see at the bottom.

Thanks
 
stevemilw said:
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 textbook gives as you can see at the bottom.

they look the same to me :confused:

(with X-1/2 instead of 1/√X )
 
ooooh, i feel really stupid now.
I didnt realize that x^-1/2 was 1/sqrt x

God, you wouldn't believe the amount of hassel that's given me!

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

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