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Ronalds
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Homework Statement
The Magnus formula is used for calculating the saturated water-vapour pressure Ew at temperature t. The average of the 10 repeated measurements of air temperature is 22.27 ˚C with experimental standard deviation s(t)=0.09 ˚C. The permissible error of the thermometer is ±0.3 ˚C. The average of the 10 repeated measurements of relative humidity h is 38.9 %rh with corresponding standard deviation of the mean sA(h)=0.10 %rh. The correction of the hygrometer is -1.6 %rh and the corresponding expanded uncertainty is 1.2 %rh (k=2). The value of the molar mass of water-vapour Mw=0.018015 kg mol-1 and the value of the universal gas constant R=8.3145 J mol-1 K-1 . For calculations you can assume that Ew and t are fully correlated. Please calculate the absolute humidity Dw and estimate its expanded uncertainty at confidence level P=95%.
Please help at least somehow with this task which is hard to solve! I know that solution is too much to ask, and will appreaciate every help!
Homework Equations
In order to calculate the absolute humidity of air [g/m3] the following simplified equation can be used:
Dw = (1000 * Ew (t) * Mw * h) / (R * (t + 273.15))