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!

Finding total kip/ft

  1. Sep 26, 2013 #1
    1. The problem statement, all variables and given/known data

    Number 1-5 from here http://www.slideshare.net/hotman1991/met-302-chapter-01

    How do I deal with the 1.5 kip/ft? Am I right to think that the smaller arrows to the left mean that the kip/ft there is less than 1.5kip/ft? How can I find kip/ft at a given point along the horizontal axis?
    * I know that the answers are given, however I do not understand it.

    2. Relevant equations

    Possibly A = 1/2(b*h) = 1/2(12)(1.5) = 9 kips

    EDIT: I also found the same 9kip/ft through ∫(1.5x/12)dx from 0 to 12.

    3. The attempt at a solution

    The answers use area to get total (?) kips. I sort of understand why they would do that, something like integrating from 0-12 ft. However, I do not understand how they found 9kips at 4ft from B, or why they put the 9 kips there at 4ft.
     
    Last edited: Sep 26, 2013
  2. jcsd
  3. Sep 26, 2013 #2

    SteamKing

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    The triangularly distributed load is 0 kip/ft on the left side and 1.5 kip/ft on the right side.

    The total load is not 9 kip/ft, it's 9 kips, period.

    What is the location of the center of gravity of a right triangle?
     
  4. Sep 26, 2013 #3
    Yes, sorry about the units mix up.

    Ah, I see what you mean. So we take it as if the 9 kips is at the center of gravity... Do we ignore the vertical part of the center of gravity? The answer seems to do so (both equations and equations don't take it into account).
     
  5. Sep 26, 2013 #4

    SteamKing

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    The load is along the length of the beam. You are confusing the graphical representation of a distributed load with how the load is actually distributed. In other words, the vertical component doesn't exist.
     
  6. Sep 26, 2013 #5
    Whoops. Thanks for reminding me. I appreciate all of your help.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted