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Homework Help: In desperate need of help with this statically indeterminable problem

  1. Dec 17, 2011 #1
    1. The problem statement, all variables and given/known data

    http://img855.imageshack.us/img855/5648/fbds.png [Broken]

    Basically I am analysing the human leg in the given position. I need to find the force (F) which is exerted at point C, when the person is in such a position. Point B represents a "pin connection" at the ankle, body AB is the shin, BC - the thigh. All masses and distances are known.

    2. Relevant equations

    These are the main equations of static equilibrium for the two bodies.

    http://img600.imageshack.us/img600/6118/equilibriums.png [Broken]

    Unknowns: Bx,By,N,Ax,Mb,Mc,F.

    3. The attempt at a solution

    That was my attempt, I am not looking for a numerical solution, just some help with how should I continue... If this truly is a statically indeterminable problem, I don't think that the method of superposition or other deviation related methods could help... Any input would be greatly appreciated. Even if it includes pointing out a stupid mistake of mine.. :D Thanks, guys!
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Dec 17, 2011 #2
    "Point B represents a "pin connection" at the ankle, body AB is the shin, BC - the thigh."

    If B is the ankle and AB the shin, how can BC be the thigh?
     
  4. Dec 17, 2011 #3
    Omg, stupid mistake, sorry. A is the pin joint.
     
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