1. Not finding help here? Sign up for a free 30min 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!

Work and Kinetic Energy Problem for Pump

  1. May 1, 2007 #1
    1. The problem statement, all variables and given/known data
    A pump is required to lift 800 kg. ( about 200 gallons) of water per minute from a well that is 14.0 m deep and eject it with a speed of 30 m/s
    a.) how much work is done per minute in lifting the water?
    b.) how much in giving it kinetic energy?

    2. Relevant equations
    W = Fd
    F = ma
    a = V/t
    KE = 0.5(m)v^2


    3. The attempt at a solution
    a = v/t = (30 m/s)/(60s) = 0.5 m/s^2

    F = ma = 800(0.5) = 400 N

    W = (400 N)(14 m) = 5600 J

    My answer for letter a. W = 5600 J

    KE = 0.5(m)v^2 = 0.5(800)(30) = 12000 J

    My answer for letter b. KE = 12000 J

    Am i right? please let me know if there are any mistakes. Thank you...
     
  2. jcsd
  3. May 1, 2007 #2
    a) [tex] W = mgh+ \frac{1}{2} mv^2 = 800kg*14m*9.81ms^{-2}+\frac{1}{2}*800kg*(30m/s)^2 = 469872J [/tex]
    b) [tex] \frac{1}{2}mv^2 = \frac{1}{2}*800kg*(30m/s)^2 = 360000J [/tex]
     
  4. May 1, 2007 #3

    hage567

    User Avatar
    Homework Helper

Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Work and Kinetic Energy Problem for Pump
Loading...