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!

A simple Fluid Dynamics/Pressure HW question

  1. Apr 21, 2015 #1
    1. The problem statement, all variables and given/known data
    A piston of cross-sectional area a is used in a hydraulic press to exert a small force of magnitude f on the enclosed liquid. A connecting pipe leads to a larger piston of cross-sectional area A (the figure). If the piston diameters are 3.63 cm and 50.7 cm, what force magnitude on the small piston will balance a 41.8 kN force on the large piston?

    2. Relevant equations
    P=F/A

    3. The attempt at a solution
    So I'm pretty sure I'm doing this right especially since we did a similar one in class so I think it might just be a math error here's what I did.

    For the smaller side Ps = Fs/as

    For the larger side Pb = Fb/Ab

    Ps = Pb

    Fs/as = Fb/Ab

    Solve for Fs
    Fs = Fb/Ab * as

    Plug in values (Fb 41.8kN = 41800N) (Ab 50.7cm =.507m) (as 3.63cm = .0363m)

    Fs = (41800/.507)*.0363 = 2992.78N WileyPlus says its wrong though, so did I make a mistake?
     

    Attached Files:

    Last edited: Apr 21, 2015
  2. jcsd
  3. Apr 21, 2015 #2
    For some reason you plugged in the diameters instead of the areas.
     
  4. Apr 21, 2015 #3
    I guess I did. I didn't even notice it said diameters thanks. I must remember to read more thoroughly next time.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: A simple Fluid Dynamics/Pressure HW question
  1. Simple fluid dynamics (Replies: 10)

Loading...