- #1
Redfire66
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1. Determine the relative and absolute uncertainties of R-2 if R is measured to be 4.5 ± 0.005 m
2. The attempt at a solution
So according to what I know so far, multiplication and division of uncertainties requires the addition of relative uncertainties...
First I tried to get the relative uncertainty of R-2. I assumed that a power of negative 2, that would be division twice (which I got to be 0.005/4.5 + 0.005/4.5 or just 2*(0.005/4.5)).
According to the CAPA answers, the resulting answer I got was the correct relative uncertainty of R-2.
The relative uncertainty I got had a value of 2.3 x10-3 or just 2x10-3
But then when I tried to solve for the absolute uncertainty
I multiplied this to the value of 4.5
4.5-2*2*(0.005/4.5)
= 1x10-4 m-2
However the the question posted on the CAPA problems tells me that my answer is incorrect. I'm not sure what I did wrong; the system didn't allow more than 1 digit so I rounded it down from 1.2
2. The attempt at a solution
So according to what I know so far, multiplication and division of uncertainties requires the addition of relative uncertainties...
First I tried to get the relative uncertainty of R-2. I assumed that a power of negative 2, that would be division twice (which I got to be 0.005/4.5 + 0.005/4.5 or just 2*(0.005/4.5)).
According to the CAPA answers, the resulting answer I got was the correct relative uncertainty of R-2.
The relative uncertainty I got had a value of 2.3 x10-3 or just 2x10-3
But then when I tried to solve for the absolute uncertainty
I multiplied this to the value of 4.5
4.5-2*2*(0.005/4.5)
= 1x10-4 m-2
However the the question posted on the CAPA problems tells me that my answer is incorrect. I'm not sure what I did wrong; the system didn't allow more than 1 digit so I rounded it down from 1.2
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