Hello Experts:

I need some assistance with applying a formula/equation (based on calculating "uncertainty".

As the saying goes "A picture is worth a thousand words", I've attached a spreadsheet that contains the following:

1. Calculation of sound in sea water (this is complete)

2. Reference to website that includes equations for "uncertainty"

Based on step #2, I need to calculate the value for uncertainty based on a) multiple inputs and b) single input.

Given the listed equations (on NIST's website), how to I calculate a) and b) in MS-Excel?

Thank you in advance,

EEH

Calculate-uncertainty.xlsx
Not really my field, but it seems clear to me that

u(xN)is theuncertaintyin the measurement ofxN, not the measurement itself.For example, if your temperature estimate is (2 ± 0.5) °C, then u(T) is 0.5.

It seems that you multiply these by the squares of the constants in the original formula, so the first term

a1^2*u(x1)^2is:4.591^2 * 0.5^2I'm not sure what happens when the estimated value is raised to a power, as in the terms like (5.304*10^-2)*(T

^2)It's even trickier when they are exponentiated and multiplied:

(7.139*10^-13)*T*(D^3)

All the best,

Graham