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I Error propagation estimation

  1. Apr 15, 2016 #1
    I have a physical quantity A defined as ##A=(74.5 B^2*(M+N))^{1/3}##

    where B, M, N and relative uncertainties are given. And M and N are dependent on B.
    Could you show me how to calculate and estimation for the uncertainty on A?

    Thanks a lot
    Last edited: Apr 15, 2016
  2. jcsd
  3. Apr 15, 2016 #2

    Vanadium 50

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    You will need to know the correlation between the uncertainties on M and N and the uncertainties on B. If you think this is small, you can treat them as independent.
  4. Apr 15, 2016 #3
    M and N are function of B (ie for example ##log M=(0.755 \pm 0.059)*log B+(0.416\pm 0.024)## The value of B is given by a software, and its uncertainty is 0.0002.
    The values of M and N are extimated using relations like the one that I have just written, and it is assumed that the error is 15%.
    How can I estimate the uncertainty on A?
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