Hello, I just need some help about doing university 1st year practicals. Particularly error analysis, what's the easiest way to do it? We were given huge formulas on how to work out the errors, but I can't understand anything. At high school we used to do things like(adsbygoogle = window.adsbygoogle || []).push({});

error=(instrument uncertainty)/(measurement). So can I still use this?

What about standard deviation? I was told sd is roughly = error.

so the true value X=measurement+-error (stated above)?

And then usually in practicals we have things like functions of x -> f(x). And we need to calculate the error in the f(x). Again from high school I remember that when we add, subtract, multiply, ?divide? values, the errors add up. But what if we have something like

f(x)=square root(x)? then what's the value of the error in f(x)

I had a similar function at my last practical and I couldn't work out the error on f(x). The demonstrator first told me something about derivaties and errors, then gave a huge formula to try as a different method, then I understood that he didn't really know what he was doing (because eventually he said a computer software could have worked it out from the graph of f(x), but I was supid to use excel that doesn't do it...). And after a day long practical I got average mark, instead of a good one because of this minor slip.

Anyway, how do YOU work with errors? I'm particularly interested in opinions of people who have done many practicals and can suggest an easy to understand way (or even algorithm: 1) 2) 3)... in working out errors or tips).

Thank you

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# How to do physics practicals properly? (error analysis help needed)

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