## Réaumur to Rankine (ºRé to ºR) formula

**Rankine** = (**Réaumur** * 2.25) + 491.67

## About Réaumur

Réaumur is a temperature scale that were widely used in the past, particularly in Europe. The Réaumur scale, named after the French physicist René Antoine Ferchault de Réaumur, was developed in the early 18th century. On this scale, the freezing point of water is set at 0°Ré and the boiling point at 80°Ré, with the scale divided into 80 equal parts or degrees. The Réaumur scale was commonly used in scientific research and engineering applications in Europe until it was gradually replaced by the Celsius scale.

While the Réaumur scale is no longer commonly used, it played a significant role in the history of temperature measurement. The Celsius scale, on the other hand, has become the international standard for temperature measurement, providing a common language for scientists, engineers, and individuals worldwide.

## About Rankine

Rankine is a unit of temperature measurement commonly used in engineering and thermodynamics. It is named after the Scottish engineer and physicist William John Macquorn Rankine, who made significant contributions to the field of thermodynamics in the 19th century. The Rankine scale is an absolute temperature scale, similar to the Kelvin scale, but with a different zero point.

The Rankine scale is based on the Fahrenheit scale, with the zero point set at absolute zero (-459.67°F). This means that the Rankine scale has the same size degree as the Fahrenheit scale, but starts at a different point. To convert between Rankine and Celsius, one must first convert from Celsius to Kelvin by adding 273.15, and then convert from Kelvin to Rankine by multiplying by 1.8. The formula for this conversion is: Rankine = (Celsius + 273.15) × 1.8.

While the Rankine scale is not commonly used in everyday life, it is widely used in engineering and thermodynamics, particularly in the United States. It is often used in calculations involving temperature differentials, such as in the study of heat transfer and energy systems. Understanding the Rankine scale and its conversion to Celsius is important for engineers and scientists working in these fields, as it allows for accurate and consistent temperature measurements and calculations.