Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Moment of force

  1. Aug 19, 2005 #1
    This question may sound silly to all of you brainy guys out there but I am one silly guy.
    While calculating the moment of a force how do you choose which component (horizontal or vertical) to choose? I know that M=F*d. Its confusing when authors sometimes use the veritical and sometimes the other component.
    Also please let me know if there is a nice little websites where such basic conepts could be found.
     
  2. jcsd
  3. Aug 19, 2005 #2

    FredGarvin

    User Avatar
    Science Advisor

    The component you need is whatever component is perpendicular to the radius you are using as the distance. For example, imagine a circle. If you draw a radius from the center to the 3 o'clock position, then the vertical component will produce the torque. If you draw a radius from the center to the 6 o'clock position, then it would be the horizontal component. The radius dictates the component used.

    When in doubt, hyper physics is a great website:
    http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
     
  4. Aug 20, 2005 #3
    inother words you would use the distance that is shortest that makes a rright angle from the line of action to the position of application
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?