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!

Calculating net torque!

  1. May 19, 2009 #1
    1. The problem statement, all variables and given/known data
    This is the problem: http://session.masteringphysics.com/prob [Broken]...

    A squar emetal plate .180 m on each side is pivoted about an axis through point O at its center and perpendicular to the plate. Calculate the net torque about this axis due to the three forces shown in the figure if the magnitudes of the forces are F1=18.0n, F2=26.0N, and F3=14.0N. The plate and all forces are in the plane of the page.

    3. The attempt at a solution
    Okay so this problem looks simple enough.... but I get the wrong answer.

    So here's what I did. I individually calculated the torques for each force.

    Torque for F1: (18.0)(.09)=1.62
    Torque for F2: (26.0)(.09)=2.34
    Torque for F3: (14.0)(sin45)(.09)=.89095

    Then I find the net torque by....
    -F1+F2+F3=1.61N m

    but the answer should be 2.5N m.

    Can anybody tell me what I'm doing wrong?
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. May 19, 2009 #2
    I can't open your link.
  4. May 19, 2009 #3


    User Avatar
    Science Advisor
    Homework Helper

    Welcome to PF!

    Hi jghlee! Welcome to PF! :smile:

    I can't see the picture :cry: (you've chopped off the end of the url :rolleyes:) …

    but since you're exactly 0.89 out, my guess :wink: is that you've multiplied by sin45º instead of dividing by it! :smile:
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Calculating net torque!
  1. Net Torque (Replies: 5)

  2. Calculating net torque (Replies: 2)