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Ten Things You Maybe Didn't Know About the Degree Rankine

1. It’s an absolute temperature scale

The Rankine scale, like the Kelvin scale, is an absolute temperature scale. This means it starts at absolute zero, the point where molecular motion stops completely. No negative temperatures here!

2. Named after William John Macquorn Rankine

The Rankine scale was developed in the 19th century by Scottish engineer and physicist William Rankine. He was one of the early pioneers in thermodynamics, which is why his name lives on in this temperature scale.

3. It’s used mostly in the U.S. engineering world

While the Rankine scale isn’t used much in daily life, it’s common in certain industries—especially in the United States. You’ll see it in fields like thermodynamics and engineering, especially when dealing with heat engines and refrigeration cycles.

4. It’s like Fahrenheit, but with absolute zero

If you know Fahrenheit, Rankine will be familiar. The difference is that while Fahrenheit starts at 32°F for water’s freezing point, Rankine starts at absolute zero (0°R), which is equivalent to -459.67°F.

5. Water freezes at 491.67 °R

In the Rankine scale, water freezes at 491.67 °R and boils at 671.67 °R. These values match up with the freezing and boiling points of water, but in the absolute temperature system that Rankine created.

6. It's not as common as Kelvin, but still useful

Even though the Kelvin scale has largely replaced Rankine in most scientific fields, Rankine still sees use in some engineering and thermodynamics applications, especially in the United States. It's handy for working with heat systems that use Fahrenheit.

7. It’s easy to convert from Fahrenheit

One of the best parts about the Rankine scale is that it’s directly related to Fahrenheit. To convert Fahrenheit to Rankine, you just add 459.67 to the Fahrenheit temperature. Simple, right?

8. Important in thermodynamics

When you’re studying thermodynamics, Rankine is often the scale you’ll encounter. Many equations for energy, work, and heat transfer use Rankine, since it’s an absolute scale that helps avoid negative values in calculations.

9. It’s still used in some aerospace and mechanical engineering

In certain technical fields like aerospace and mechanical engineering, Rankine is still employed for temperature-related calculations. For example, when engineers deal with heat engines or rocket propulsion, Rankine often makes an appearance.

10. It’s not really for everyday use

Unlike Celsius or Fahrenheit, you’re not likely to hear about Rankine when talking about the weather. But for those working in specific scientific fields, it’s an essential part of the toolkit.