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Physics uncertainty problem

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    • Thread Starter

    Using a micrometer screw gauge, I get 3 values for the diameter,d, of a wire each with +/- 0.01mm.
    What's the uncertainty for the average value for d?

    Then I have to use this average value in (πd^2)/4=A. What's the % uncertainty of A?

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    Just quoting in Puddles the Monkey so she can move the thread if needed
    (Original post by Puddles the Monkey)

    When you've taken repeat readings, the correct way to determine the percentage uncertainty is:

    ( (half the range) / (average value) ) * 100

    That would give you the percentage uncertainty in d. You then double this to get the uncertainty in A (due to the d being squared).

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