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: At what speed is the water in the hose moving?

  1. Nov 28, 2007 #1
    1. The problem statement, all variables and given/known data

    A nozzle of inner radius 1.03 mm is connected to a hose of inner radius 7.97 mm. The nozzle shoots out water moving at 25.5 m/s.
    (a) At what speed is the water in the hose moving?
    42.589 cm/s
    (b) What is the volume flow rate?
    84.989 cm3/s
    (c) What is the mass flow rate?

    2. Relevant equations

    3. The attempt at a solution

    I have found the speed of the water and the volume flow rate. I do not know how to find the mass flow rate though. Can anyone help me?
  2. jcsd
  3. Nov 28, 2007 #2


    User Avatar
    Science Advisor
    Homework Helper

    Mass flow rate and volume flow rate are connected by the density of water, right? Since that is mass/volume.
  4. Nov 28, 2007 #3
    Part of Bernoulli's Principle is that the mass that leaves the pipe, must be the same as the mass that enters the pipe.
  5. Nov 28, 2007 #4
    I am still confused on how to find this though. do i just multiply by Rho of water?
  6. Nov 28, 2007 #5
    I cant get this one either...i know they are connected by the density but i dont know what to do with the density
  7. Nov 28, 2007 #6


    User Avatar
    Science Advisor

    Mass flow rate = Volumetric flow rate times the fluid's density.

    Volumetric flow rate = fluid velocity times the cross-sectional area.
  8. Nov 28, 2007 #7
    ahh i just was not converting right thanks for the help!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook