1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Poiseuille question

  1. Apr 11, 2017 #1
    1. The problem statement, all variables and given/known data

    A large tank contains oil with a viscosity of η = 7.5 Pa s. The tank has walls and floor which are 2 cm thick, but there is a small circular hole at the base of the tank through which oil is leaking. The fluid pressure at the base of the tank is 126 kPa (atmospheric pressure is 101 kPa) and the radius of the hole is 1.5 mm. What is the volume flow rate at which the oil is leaking out of the tank (in m3 s −1 )?

    (A) 1.2 × 10−3 (B) 7.1 × 10−4 (C) 2.7 × 10−5 (D) 4.1 × 10−6 (E) 3.3 × 10−7
    2. Relevant equations
    Poiseulle law equation (maybe)

    3. The attempt at a solution
    I'm pretty sure this has to do with Poiseulle's law, because of the variables. I have all variables for the P law equation (given in the equation) except length (and the needed flowrate). I do have trouble with 2 variables being unknown, so a little help with that would be greatly appreciated :)
  2. jcsd
  3. Apr 11, 2017 #2
    You do know the length.
  4. Apr 11, 2017 #3
    Oh dang, you're right, the length was 0.02m. Don't ask me how long I was on this question and didn't click. Thanks!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted