Hi everyone! I wanted to know how it is determined uncertainty ? i watched some lesson but i didn't understand if it is a variable chosen from who is making the measure of that depends on the tool that i use for the measure ?
I did not say that, but it is true.Ahh ok ok i understand, you are saying that to be more precise for certain measures i can reduce the uncertainty by doing it a number of time and then use the new uncertainty.
Ok i know about rounding up! But what about significant figures ? i should keep in mind of them in every calculation ??I did not say that, but it is true.
Round the final value and nothing in between - and if you want to do it properly, use gaussian error propagation. Without knowing the values for x,y,z, it is impossible to tell which part will be relevant for the total uncertainty.
In addition, you cannot simply give the result with 2 significant figures.
Significant figues (relative uncertainties) can be a handy tool to evaluate the uncertainty of products, but they are usually useless for sums. Gaussian error propagation is more the general tool, it works for both (and many more operations).Ok i know about rounding up! But what about significant figures ? i should keep in mind of them in every calculation ??
I am sure you can find many websites with examples. It is a standard questions.Can you make me an example with the formula i gave you or with a formula you choose and use random numbers just to make me understand how the calculations work with significant figures and if i have to count them after every calculation or only in certain situation?