Uncertainties of Dimensionless Units

Thread starter Qube
Start date Mar 3, 2012
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Uncertainties Units

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When expressing the uncertainty of a dimensionless quantity, such as the coefficient of friction, it is acceptable to write it as 0.40 ± 0.02 instead of including unnecessary decimal places. The precision of the reported value should match the uncertainty to avoid confusion. Including excessive digits can mislead the interpretation of the measurement's accuracy. It's important to ensure clarity and simplicity in reporting uncertainties. Properly formatted, the uncertainty communicates the reliability of the measurement effectively.

Mar 3, 2012

Qube

Gold Member

I have a physics project, but how do I express the uncertainty of a dimensionless quantity?

E.g. how do I express the uncertainty of the coefficient of friction?

Do I just write 0.403 ±0.02?

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Mar 3, 2012

BluFoot

The way you write uncertainty is fine. But there's not much point in putting the "0.003" if it's ± 0.02... Might as well write: 0.40 ± 0.02

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