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Homework Help: Normal Stress In A Simple Beam

  1. Jun 17, 2013 #1
    1. The problem statement, all variables and given/known data
    In a prismatic bar (same cross sectional area throughout the entire length), the load applied to both ends is 100 N causing the member to be in tension. If the cross sectional area of the member is
    5 cm2. What is the normal stress in the in kPa?

    2. Relevant equations
    stress = force / area

    3. The attempt at a solution

    I first tried without looking at the units, and got 20, which is wrong. I next tried converting everything to m2 to get the answer is pascals the convert to kPa. I got 200 for my second answer. What am I doing wrong? This seems like such a simple problem!
  2. jcsd
  3. Jun 17, 2013 #2


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    What are the derived units of a Pascal? Are they N/m^2 or N/cm^2?
  4. Jun 17, 2013 #3
    They are N/m^2. I used an online converter to check, so I confused about what I did wrong.
  5. Jun 17, 2013 #4
    Is the bar supported in the middle? If so, should the force be 100 or 200 N?
    How did you get 20?
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