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Calculating uncertainty

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calculating uncertainty
I have a lab where I have to calculate the theoretical value of R using the following equation and then find the uncertainty in R.

R=(xCOS(y))*((-xSIN(y)-SQRT((xSIN(y))^2-2*-9.8*z))/-9.8)
*I know the values of x,y,z and their respective uncertainties.

The problem is that we have only learned basic uncertainty rules (i.e. for multiplication/division you add the %uncertainty, for addition/subtraction you add the absolute uncertainties). This is much more complicated since I have to deal with SIN/COS and square roots. I was searching around and it seems that I have to calculate the partial derivative or differentials. I am not familiar with differentials and I have no idea how to solve this problem. If anyone can offer any help whatsoever it would be greatly appreciated or anywhere where I can find this information.

i'm using excel if that makes any difference.
 

Answers and Replies

nicksauce
Science Advisor
Homework Helper
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Do you know how to calculate a derivative? If so, it shouldn't take more than a minute to learn how to take a partial derivative.
 
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take extremes!
simple and perfect
 
6
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i know how do to partial derivatives but is the uncertainty just the partial derivative of the equation.
 

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