Calculating Uncertainty in Averages for Scientists

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AI Thread Summary
In the discussion about calculating uncertainty in averages for the Franck-Hertz experiment, the user seeks guidance on determining the uncertainties associated with the differences between minimum values A, B, C, D, and E. The values and their respective uncertainties are provided, and the user aims to calculate the average of these differences. The "sum of squares" rule is mentioned as a method for calculating uncertainty, along with a simpler approach that sums the maximum deviations. The conversation highlights the importance of accurately propagating uncertainties in scientific measurements. Properly applying these methods will enhance the reliability of the experimental results.
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Homework Statement


In my lab we are doing Franck Hurtz experiment with heated mercury and electron beams. We already took data but i need a little help. I have the locations of the minimums A B C D and E, and each point has it's own uncertainty. a b c d and e. What i needed to find was the difference between each min and the next, so A-B, B-C... and then find the average of each these differences. I don't know how to do the uncertainty for my calculations.


Homework Equations


My actual values are
1.4
1.94
2.43
2.98
3.66
With uncertanities (in order)
0.003686
0.008077
0.002263
0.009459
0.003834


The Attempt at a Solution

 
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I would say that the most general rule is the "sum of squares" rule,
(\Delta d)^2 = (\Delta x)^2 + (\Delta y)^2
where d = x - y is the difference of two independent quantities x and y.

However, I think that
(\Delta d) = (\Delta x) + (\Delta y)
is also commonly used, giving the "rough" estimate that the deviation from the mean is at most the sum of the two maximal deviations.
 
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