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Homework Help: Calculating uncertainty

  1. Apr 15, 2008 #1
    calculating uncertainty
    I have a lab where I have to calculate the theoretical value of R using the following equation and then find the uncertainty in R.

    *I know the values of x,y,z and their respective uncertainties.

    The problem is that we have only learned basic uncertainty rules (i.e. for multiplication/division you add the %uncertainty, for addition/subtraction you add the absolute uncertainties). This is much more complicated since I have to deal with SIN/COS and square roots. I was searching around and it seems that I have to calculate the partial derivative or differentials. I am not familiar with differentials and I have no idea how to solve this problem. If anyone can offer any help whatsoever it would be greatly appreciated or anywhere where I can find this information.

    i'm using excel if that makes any difference.
  2. jcsd
  3. Apr 15, 2008 #2


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    Do you know how to calculate a derivative? If so, it shouldn't take more than a minute to learn how to take a partial derivative.
  4. Apr 15, 2008 #3
    take extremes!
    simple and perfect
  5. Apr 15, 2008 #4
    i know how do to partial derivatives but is the uncertainty just the partial derivative of the equation.
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