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Homework Help: Equilibrium problem

  1. Aug 6, 2004 #1
    i am having a problem with this question can someone help me please

    Determine the reactions a piont "A" and "B"
    please note A is a moving support
    and B is a fixed support

    look at attached file for the problem

    please reply with a full mathematical answer

    Attached Files:

    • mat.txt
      File size:
      627 bytes
    Last edited: Aug 6, 2004
  2. jcsd
  3. Aug 6, 2004 #2


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    Please read the various stickys regarding homework help.
  4. Aug 6, 2004 #3
    -Resolve horizontal forces.
    -Resolve vertical forces.
    -Resolve moments.

    Remember that if this is in equilibrium the force acting left and right must be equal.
    Forces acting up and down must be equal.
    The anti clockwise and clockwise moments at any given point must be equal.

    Where exactly are you having difficulty?
  5. Aug 6, 2004 #4
    i don't now how to resolve the moments with the additional horizontal force
  6. Aug 6, 2004 #5
    I cant see your attachement.
  7. Aug 7, 2004 #6
    Hmm, the link has gone down so i'm sorry i can't be more specific.

    If a force is acting upwards or downwards from the point at which you are resolving, it is the horizontal (do not include vertical) distance to the force (so the point to measure to would be exactly above or below the force). multiplied by the force.
    Similarly, if a force is acting horizontally from the point at which you are resolving it is the vertical distance multiplied by the force magnitude.

    If the force is acting at an angle you can resolve everything into x and y components, to make it much easier to calculate.
    For example: For a 10N force acting at 23 degrees, the horizontal force is 10cos23, while the vertical force is 10sin23. From my memory though this doesn't seem to be a problem in your question.

    If you're still having trouble and the link is back up i'll try to assist you further.
    Have fun.
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