The Celsius temperature scale is an interval scale [0] which means that it is possible to calculate differences but not ratios. The Kelvin temperature scale is a ratio scale [0] (it has an "absolute zero") that allows to do that.
Beside that if there are uncertainties involved, one should do proper propagation of uncertainty anyways. [1]
[0] https://en.wikipedia.org/wiki/Level_of_measurement
[1] https://en.wikipedia.org/wiki/Propagation_of_uncertainty
This is talking about the error in the difference between two values with the same units though. For temperature, it wouldn’t matter if you’re using C, K, or F for your starting values, the % error of the difference would be the same (I think).
Yes.
What would make a difference is to change to https://en.wikipedia.org/wiki/Thermodynamic_beta
(Essentially the same difference as miles per gallons vs litres per 100 km.)
Yes, because there is an arbitrary choice of origin which renders the relative error dependant on units. If you're measuring a length, for instance, or an interval of time, the relative error is independent of which units you choose. If you're measuring e.g. a distance to some point, then again you have an arbitrary choice of origin.
It gives a disproportionate meaning to 0 without real physical consideration, eg:
- 0.1⁰C ± 0.1 (wow 100% relative error) - 273.25K ± 0.1 (meh 0.04% relative error)