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Homework Help: Explaining feet pr. 100ft?

  1. Jun 21, 2006 #1
    I have an equation for calculting head loss in pipes, and the result comes out as ft/100ft. I don't understand this unit, as I was expecting a unit more in the form of Pa, psi, or something to that effect. If someone can explain it to me I would appreciate it :-)
  2. jcsd
  3. Jun 21, 2006 #2


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    The units are in terms of head loss per 100 ft of pipe, not pressure drop. Since it is head instead of pressure, the units are a length per length of pipe. It does look a bit wierd, admittedly.
  4. Jun 21, 2006 #3
    looks like a typing error, if it is ft/100ft then the ft will cancel out to get 100, the head loss to me sounds like a rate of something, so I would say it should be psi/100ft if you are using those types of units, this is what I think anyway
  5. Jun 21, 2006 #4


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    It's not a typing error. It's a perfectly sensible unit, especially if you want to decide, for instance, how high to place a storage tank for a gravity feed.

    To convert to Pa per 100 ft. of pipe, multiply the given number by 1000(kg/m3)*9.8(m/s2)*0.30(m/ft).
  6. Jun 21, 2006 #5
    i've never seen that used before, must be because I am english or because I am thick lol I apologise for my false statement before
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