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: Hydraulic lift/Pressure

  1. Nov 4, 2007 #1
    1. The problem statement, all variables and given/known data
    Piston 1 in Figure P9.24 has a diameter of 0.32 in.; Piston 2 has a diameter of 2.0 in. In the absence of friction, determine the force, , necessary to support the 500 lb weight.


    2. Relevant equations


    3. The attempt at a solution
    I solved for F1 using the above equation and got 12.8. THIS IS WRONG Is this because the column of fluid is higher in the larger piston? So i have to factor in the weight of the higher water as well? Can someone please point me in the correct direction?

  2. jcsd
  3. Nov 5, 2007 #2


    User Avatar
    Homework Helper

    you got the force that the piston at 1 exerts upwards... what force does the hand need to exert to keep the piston from moving.. use torque.
  4. Nov 5, 2007 #3

    would the radius be from the hand to the center of piston 1?
  5. Nov 5, 2007 #4


    User Avatar
    Homework Helper

    you want the torque about the point next to the piston 2. so torque due to the F force is F*12.0in clockwise... what is the torque due to the pressure force...
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook