1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    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!

Displacement from an Acceleration Time Graph

  1. Feb 4, 2016 #1


    User Avatar

    1. The problem statement, all variables and given/known data
    2. Relevant equations
    Kinematic equations
    t = 18s when the velocity is back to 54km/h or 15m/s
    at t = 2, V = 13.3 m/s
    at t = 4.5, velocity is 1.5 m/s
    at t = 1, V = 15m/s

    3. The attempt at a solution
    I have solved the first part and I have the time at which it is 54km/h again, but now I'm trying to figure out
    the position. I think I could make a v-t graph and find the area under that curve, but it seems like that would be too hard to accurately represent the graph. Is there any other way to find displacement? I've tried
    xo = vot + 1/2at2 but that doesn't seem to help
    I also tried
    x = xo + vt, but I get 270m as an answer. The correct answer is 178.8, but I just want to understand how to do it. Any help would be much appreciated!

    Attached Files:

  2. jcsd
  3. Feb 5, 2016 #2


    User Avatar
    Homework Helper

    What you can try is set up a(t) functions for the two regions and integrate the functions twice wrt time.
  4. Feb 5, 2016 #3


    User Avatar

    Staff: Mentor

    You'll have to show your attempt(s) in detail.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted