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Homework Help: Uncertainty of a Rate

  1. Nov 8, 2005 #1
    Let's say that I have a long lived radio active isotope and I make 10 one second measurements of the disintegration. My measurements are as follows:
    Code (Text):
    3, 0, 2, 1, 2, 4, 0, 1, 2, 5
    How many one second measurements would I have to make to get an uncertainty of 1%?

    The answer is 5,000, but I have no idea how to get it.
     
  2. jcsd
  3. Nov 8, 2005 #2

    jim mcnamara

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    Staff: Mentor

    I'm not sure what you mean but the margin_of_error which sometimes is called the uncertainty can be calculated knowing only the number of observations. 1 divided by the square root of the number of observations.

    for 5000 it is about 1.4% which is 1 / sqrt( 5000 )
     
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