Optimizing Error Calculations for Coursework

AI Thread Summary
For error calculations in coursework, using the average (mean) of repeated measurements is recommended. In the provided example, the standard deviation can be calculated to estimate random error, indicating measurement uncertainty. If measurements are normally distributed, about 68% will fall within one standard deviation of the average. When measuring weight on a balance with two decimal places, an error of ±0.005 is appropriate. Understanding these concepts helps in accurately reporting measurement uncertainties.
blackcat
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for my coursework I'm meant to do error calculations.

say i measured a distance between two things five times and got these results:

0.104
0.104
0.104
0.108
0.108

now I've got to use this distance for my calculations. would you recommend i use an average (mean)? i suppose that's a stupid question.

my teacher also says: "You would get an estimate of random error by repeating results enough times to get a standard deviation for the random error.
"

so does this mean, for my example listed above, that i would say the error is (+-) value of s.d?
 
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The standard devition is often used as an indication of the uncertainty of the measurement. You would use the average of your measurements. If the errrors are truly random, the values of a large number of measurements would be normally distributed and about 68% of the measurements would be within 1 s.d of the average.

http://www.has.vcu.edu/psy/psy101/forsyth/normal.gif
 
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ok.

1) I'm sorry if this sounds stupid, but say i measure a weight on a balance that measures up to 2 dp. do i say the error is (+-)0.005.
 
blackcat said:
1) I'm sorry if this sounds stupid, but say i measure a weight on a balance that measures up to 2 dp. do i say the error is (+-)0.005.
That's what I would do :wink:
 
THANK YOU!

Also thanks for your help on my other thread, I got it.
 
blackcat said:
THANK YOU!

Also thanks for your help on my other thread, I got it.
My Pleasure :smile:
 
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