- #1

Yatty33

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## Homework Statement

I have completed a lab that uses a Wheatstone bridge to find an unknown resistance utitlizing a resistance box and a slide wire.

This will yield the unknown resistance from the following formula...

Ru = unknown resistance

Rs = known resistance from the resistance box

x = distance from 0 on the slide wire in meters

Ru = (x/(1-x))*(Rs)

So for the unknown resistance, I took 3 values of x, and Rs (because Rs changes on the slide wire as x increases)

So here's my problem. I don't know how to do partial derivatives, except in the most basic way, or how to apply the propagated error equation.

## The Attempt at a Solution

My attempt:

Error Ru = (Rs)[tex]\sqrt{}((1/(x(1-x)))^2(\sigma x)^2 + (\sigma Rs/(Rs))^2))[/tex]

With [tex]\sigma whatever[/tex] being the standard deviation.

The question here is, did I do this correctly?

If I did do this correctly, should I get one value for my error propagation for the entire series of measurments or should I get 3 different error propagations (3 different x, 3 different Rs)?

Will there be 3 different values for error propagation then?

Thanks for your help!

P.S. This is my first post, but I have been using PF for physics help the last 2 semesters, awesome website. This is the first time I've ever had to post something on here :)