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Homework Help: Finding percentage uncertaintys

  1. Mar 8, 2010 #1
    I need help on how to work out uncertianity is there a set equation for it?

    i found this on the web
    Step 1:
    Add up all your values and divide by the number of values

    Step 2:
    Subtract each value from this average value and take the absolute value from this (positive numbers)

    Step 3:
    Add up all these absolute values and divide by the number of values

    Step 4:
    Take this value and divide by the square root of the number of values you have

    This 4 step process gives you the uncertainty of the data you have collected

    is this correct?

    1) when measuring wire i got the resualts of
    0.28mm
    0.28mm
    0.28mm
    0.29mm
    0.29mm
    0.29mm
    0.28mm
    0.29mm

    The actual width of the wire said on the roll was 0.28mm and theses were taken with a electronic vernier scale which measures to 2dp of a mm. (if this is of any use)

    i also read that if the uncertainity is below what the equipment can measure it is neglecable. And i also need to know how to turn it into a percentage

    thanks in advanced
     
  2. jcsd
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