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!

Determine the work as objects moves in straight line

  1. Mar 11, 2012 #1
    1. The problem statement, all variables and given/known data
    Assume that a force acting on an object is given by F=axi+byj, where a=2.9 N/m and b=3.9 N/m. Determine the work done on the object by this force as it moves in a straight line from the origin to r=(10.0i +21.5j)

    3. The attempt at a solution
    i used the given info to calculate the magnitude of the Force. F=2.9(10)+3.9(21.5)=112.9. i then calculated the distance traveled by doing arctan (21.5/10)=23.7. W=FΔx, W=112.9x23.7=2675. which is wrong, apparently the answer is roughly 1000 J.
     
  2. jcsd
  3. Mar 11, 2012 #2

    OldEngr63

    User Avatar
    Gold Member

    Maybe you should try calculating the work directly from the definition:

    W = ∫(0,0(10,21.5) (ax i + by j). (dx i + dy j)

    =∫010 ax dx + ∫021.5 by dy

    = (a/2) x2|010 + (b/2) y2|021,5

    Complete the evaluation and see how that works out for you.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook