- #1
Bolin
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Moderator's note: Thread moved to homework section. Thus no template.
I have an exercise in which I have to calculate the Area from the following measurements:
L = 22.1 ± 0.1 cm
W = 7.3 ± 0.1 cm
Of course, A = W * L = 161.33 but since I have a measurement with just 2 significant digits the results is limited to 2,
A = 160 (or 1.6 x 102 cm).
Now I apply error propagation:
(σA)2=(σW)2(∂A/∂W)2+(σL)2(∂A/∂L)2
computing the terms, it gives σA = 2.327 cm
Now I write my answer:
160 ± 2 cm
My question is, can I have a error in a decimal place with no significant digits in that decimal place in my answer?
Should it be
161 ± 2 cm?
I have an exercise in which I have to calculate the Area from the following measurements:
L = 22.1 ± 0.1 cm
W = 7.3 ± 0.1 cm
Of course, A = W * L = 161.33 but since I have a measurement with just 2 significant digits the results is limited to 2,
A = 160 (or 1.6 x 102 cm).
Now I apply error propagation:
(σA)2=(σW)2(∂A/∂W)2+(σL)2(∂A/∂L)2
computing the terms, it gives σA = 2.327 cm
Now I write my answer:
160 ± 2 cm
My question is, can I have a error in a decimal place with no significant digits in that decimal place in my answer?
Should it be
161 ± 2 cm?