How to calculate measurement uncertainty of m. I understand I should use these formulas to calculate it if I had data of many measurements, but when have only measurement then it becomes undefined, because of 0/0 in standard deviation formula.(adsbygoogle = window.adsbygoogle || []).push({});

##u(m)=\sqrt{u_a^2(m)+u_b^2(m)}##

##u_a(m)=\frac{s(m)\cdot Student(p;n_m)}{\sqrt(n_m)}##

##s(m)=\sqrt{\frac{\sum_{i=1}^{n_m}((m_i-\frac{\sum_{i=1}^{n_m}(m_i)}{n_m})^2)}{n_m-1}}##

##u_b(m)=\frac{_\Delta X_{scale}\cdot Student(p;\infty)}{\sqrt{3}}##

Assuming that ##u_a(m)## is zero if I have only one measurement data is probably false because then uncertainty with one measurement would be smaller or equal to uncertainty with more measurements.

- p is confidence level

- ##n_m## is number of measurements.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# I Calculate measurement uncertainty? I made one measurement...

Have something to add?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**