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: Volume flow rate and mass flow rate

  1. Jan 22, 2015 #1
    Hello there, so I have answered my question from fluid systems but the answer doesn't look right ;/ and I have no idea what have I done wrong. Can you please check and correct where it's wrong ? ;) here is the question:
    A pipe contains a gradually tapering section in which its diameter decreases from 410mm to 260mm. The pipe contains an incompressible fluid of density 1000kgm- 3 and runs full. If the flow velocity is 2ms in the smaller diameter, determine the velocity in the larger diameter, the volume flow rate and the mass flow rate.

    My calculations:
    Flow rate (Q)=A1 x V1 which is equal to A2 x V2
    0.26 x 2=0.52 m/s 3 (metres per second cubed)
    V2= Q/A2 = 0.52/0.41
    V2=1.26 m/s 3
    mass flow rate (M)= Density x Q = 1000x 0.52
    M=520 kg/s

    I would really aprreciate any help :)

    Attached Files:

  2. jcsd
  3. Jan 22, 2015 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Be careful here. You were given the diameters of the pipe, not the areas. How does the area of a pipe depend on its diameter?

    See comment above.
  4. Jan 22, 2015 #3
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted