Someone probably incorrectly wrote Réaumur degrees. (Copy of Celsius but ×0.8 for some reason)
Comment on More like guidelines
xkforce@lemmy.world 10 months ago
Rankine is there twice.
ChaoticNeutralCzech@feddit.de 10 months ago
user1234@lemmynsfw.com 10 months ago
°R refers to the Réaumur temperature scale which goes from 0 for freezing and 80 is the boiling point.
chiliedogg@lemmy.world 10 months ago
And had the same zero as Kelvin.
meco03211@lemmy.world 10 months ago
And it shouldn’t have degrees like Kelvin, right?
sushibowl@feddit.nl 10 months ago
The Rankine scale is generally measured in degrees. That’s because it’s defined in terms of the Fahrenheit scale, which is also measured in degrees. i.e. 1 Rankine degree = 1 Fahrenheit degree.
This is not the case for the Kelvin scale, which is defined directly in terms of thermal energy: 1 Kelvin ≈ 1.38*10^-23 J. Coincidentally (but not really of course) this amount of thermal energy is such that an increase of 1 Kelvin corresponds to 1 degree Celsius.
This is rather pedantic, as you could easily define Rankine in terms of thermal energy as well. Some people do this and don’t say “degrees” in front of Rankine. Or, you could define the Kelvin in terms of the Celsius, and measure it in degrees.
tl:dr Rankine has degrees, but for mainly historical reasons.
P.S.: Kelvin actually also had degrees until 1968!
captainlezbian@lemmy.world 10 months ago
It does share a 0 with kelvin
And F and C share a -44
tigeruppercut@lemmy.zip 10 months ago
I thought it was -40
meco03211@lemmy.world 10 months ago
It is.
meco03211@lemmy.world 10 months ago
It’s actually -40. Not 44.
xeekei@lemm.ee 10 months ago
Not if it’s an absolute scale, no. And then it does actually agree on what 0 is with Kelvin too.