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: Torque qeustion

  1. Nov 22, 2007 #1
    1. A uniform picture frame weighing 10N is supported. The cable on the right side makes an angle of 50 with the horizontal direction. Find the tension in the cords and the magnitude of the horizontal force F required to hold the frame in the position

    2. Relevant equations
    imagine a rectangular box, the length is 0.15m and width 0.3m there is a cord hanging on straight up from the top left of the box and a cord hanging on the top right of the box at a 50 degree angle. Also there is a force F pointint to the left from the bottom right corner

    3. The attempt at a solution
    i believe this question is a torque question, but i'm not 100% sure how to start solving. i broke down the equation into X-component and Y-component
    X-comp: fcos50 - F =0
    Y-comp: fsin50 + f(left) = 10

    i'm kinda stuck after this point
    i know that torque = Fd but i don't know where my pivot point should be and so on can anyone help. thanks!
  2. jcsd
  3. Nov 22, 2007 #2


    User Avatar
    Homework Helper

    You can choose any point for the torque pivot... It's best to choose a point that makes your equations simple...

    I recommend the upper right point, because then you avoid having the trig stuff in your equation.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook