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: Determining magnitude and direction of vectors

  1. Mar 13, 2012 #1
    1. The problem statement, all variables and given/known data
    Determine the magnitude and direction θ of F1 so that the resultant force is directed vertically upward and has a magnitude of 800N.

    2. Relevant equations

    3. The attempt at a solution
    I have attached the question with diagram and my attempt at solving the question. I know that by using the equation above, F1=FR-F2-F3, however I am slightly confused as to obtaining the values for these vectors and how to approach doing that.

    Attached Files:

  2. jcsd
  3. Mar 13, 2012 #2
    Solve for F1x using the horizontal components, solve for F1y using vertical components, then take F1x and F1y to solve for F1 and θ
  4. Mar 14, 2012 #3
    Thanks for your help Joffran, I managed to solve the problem with your help, I will add the working I used to solve it tomorrow
  5. Mar 16, 2012 #4
    [itex]\Sigma[/itex]Fx=0 ----> 400cos30+F1x-(4/5)(600)=0 ----> F1x=133.6N
    [itex]\Sigma[/itex]Fy=800 ----> 400sin30+F1y+(3/5)(600)=800 ----> F1y=240N

    F1= (F1x^2+F2y^2)^.5 = (133.6^2+240^2)^.5=274.7N


Share this great discussion with others via Reddit, Google+, Twitter, or Facebook