sushibowl, 1 year 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!