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Homework Help: Thermodynamics, Linear Interpolation

  1. Mar 12, 2010 #1
    1. The problem statement, all variables and given/known data
    I have been trying to learn how to use linear interpolation to find out the data needed from the thermodynamics chart, however, the book that is assigned does not even talk about it. Could someone please explain how linear interpolation is used? Thanks
  2. jcsd
  3. Mar 12, 2010 #2


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    Homework Helper

    The assumption with linear interpolation is that the two points (x1, y1) and (x2, y2) are connected with a line. Using the two point equation of a line, we get:

    y - y1 = m (x - x1), where m = (y2 - y1)/(x2 - x1)

    Thus for x3 that is between x1 and x2, we get:

    y3 = y1 + (x3 - x1) (y2 - y1)/(x2 - x1)
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