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: Tension force on a clothesline

  1. Jul 25, 2009 #1
    1. The problem statement, all variables and given/known data
    Big Bird’ has a force of gravity on him of 720 N. He is perched on a clothesline such that the
    clothesline forms a symmetrical 'V' with the angle within the 'V' being 150degrees. What is the
    tension force in the rope on each side of ‘Big Bird’?

    2. Relevant equations


    3. The attempt at a solution

    I tried to draw a scale diagram which failed. I also tried to figure this all out but i'm really stumped.

    sin150 = x /720N
    sin150 x 720N = x
    0 = x
    I don't know what to do from there, or even if i'm doing this right?
  2. jcsd
  3. Jul 25, 2009 #2


    User Avatar
    Homework Helper

    Draw the V with two tensions acting, they are the same.

    Now split the two tensions into components. For equilibrium, sum of horizontal forces=0
    and similarly, sum of vertical forces=0
  4. Jul 25, 2009 #3
    So he (big bird) is standing on a rope and has a force straightdown in gravity, there are 2 forces of Tension, so try drawing the free body diagram (hint: the tension forces form a V and also break the tension forces into vectors after)

    Then imagine a line going through the center of big bird and think about wut the angle should be for each tension force (its not 150)

    In the end u should find tht the forces in the x-direction cancel and the forces in the y-direction are Tcos(angle) + Tcos(angle) = Fg

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