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: Equivilent Force Problem

  1. Apr 3, 2006 #1
    http://img403.imageshack.us/img403/879/problem4998tl.jpg [Broken]

    Here I resolved the forces:

    [tex]\overrightarrow{F_{A_x}} = \left(375sin30\right)N[/tex]

    [tex]\overrightarrow{F_{A_y}} = \left(375cos30\right)N[/tex]

    Here is the r vector (I think):

    [tex]\overrightarrow{r_{AP}} = \left(4\hat{i} - 3\hat{j}\right)m[/tex]

    But when I do r X F, I get something wrong, what do I have to do to solve this simple problem?
     
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Apr 3, 2006 #2
    Let the Centre of AP be M, then MP is the radius Vector I guess from what I understood after seeing the picture. You know the co-ordinate of A and P, so you can find the co-ordinates of M.
     
  4. Apr 3, 2006 #3

    nrqed

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    The y component fo your force should be negative.
    Also, in calculating the torque, the vector r should go from the axis of rotation toward the point where the force is applied.

    Patrick
     
    Last edited by a moderator: May 2, 2017
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook