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!

Equilibrium Problem

  1. Nov 14, 2008 #1
    1. The problem statement, all variables and given/known data
    Basically, the string is attached a to a wall at the top right, with a mass m hanging on the other end. It asks to find the max mass m that can hang before bottom of the rod slips.

    2. Relevant equations

    3. The attempt at a solution
    I know that Ft=mg for the hanging mass m.
    Then for the x forces on the rod: Ft=Ffs
    so usFn=mg
    But I don't know what to do with the angle 50 degrees. You have to include it somewhere right?
    I was thinking us(50)(9.8)(sin50)=m(9.8) but I don't know if that's right.


    Attached Files:

    Last edited: Nov 14, 2008
  2. jcsd
  3. Nov 15, 2008 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Welcome to PF.

    There are also torques to consider, which must sum to zero. (The angle will play a role here.)

    Also, while the tension in the vertical section of string is mg, in the horizontal section it can be something different.
  4. Nov 15, 2008 #3
    I was thinking about the torque, but don't you need to know the length of the rod to find them?
  5. Nov 15, 2008 #4


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Let the rod length be L, and see how the torque equation works out.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Equilibrium Problem
  1. Equilibrium Problem (Replies: 6)

  2. Equilibrium Problem (Replies: 5)

  3. Equilibrium Problem (Replies: 2)

  4. Equilibrium problem (Replies: 1)

  5. Equilibrium Problem (Replies: 4)