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Homework Help: Very easy questions about stress

  1. Feb 10, 2010 #1
    1. The problem statement, all variables and given/known data

    A bar of material is 1ft long and has a cross sectional area of 2 square inches. If a
    force of 10,000 lbs is put on the bar, what is the stress?

    2. Relevant equations

    stress= force (in pounds)/ area (square inches)

    3. The attempt at a solution
    this seems very easy, but the "1 foot long" in the equation is throwing me off. Ive never done these kind of questions before, so i dont know how to handle it. My gut is telling me to just do 10,000 / 2 = 5000 and the "1 foot long" is unnecessary info in there to throw you off, but then again, there could easily be some other calculation i need to do...Also, what unit would the 5000 be in (assuming that's the right answer). Thanks alot (i want to make sure i know what I'm doing, so please only answer if you are 100% sure you're right)
  2. jcsd
  3. Feb 11, 2010 #2
    I'm guessing the 1 foot long refers to another part of the question where you will have to calculate the strain. (and the change in length of the bar)
    The unit you get if you divide pounds by square inches is pounds per square inch. That is a unit of pressure, though I haven't used those units since about 1967!
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