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Homework Help: Normal force during a push up problem

  1. Oct 22, 2006 #1
    A person whose weight is W = 633 N doing push-ups.

    l=====x====l==0
    ______ _____
    0.885 0.358


    Assume L1 = 0.885 m and L2 = 0.358 m. Calculate the normal force exerted by the floor on each hand, assuming that the person holds this position.

    My work so far:
    thinking L1 + L2 = 633
    and .358Rhands=.885Rfeet; Rhands and Rfeet x and y respectivelyl

    with a little substitution .358(633-x)=.885x
    What I am having trouble is the simple math of solving this. I'm either doing something illogical or can't do simple math.
    If this is wrong please tell me, if not what do I do? Maybe I've just been working on this problem a little too long......
     
  2. jcsd
  3. Oct 22, 2006 #2
    I don't understand the diagram. Are the two positions those of his right and left hands or those of his hands and his feet?
     
  4. Oct 22, 2006 #3
    they are the hands and feet
    you are seeing a sideview of the person with the x being his center of gravity
    sorry
     
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