Rankine temperature scale
- Key People:
- William John Macquorn Rankine
- Related Topics:
- absolute temperature scale
Rankine temperature scale, scale established in 1859 by Scottish engineer and physicist William John Macquorn Rankine (1820–72), with its zero set to the theoretical temperature at which the molecules of a substance have the lowest energy (absolute zero). The Rankine (°R) scale is the absolute temperature scale related to the Fahrenheit (°F) scale, and both scales have the same size unit of temperature. The two scales are related by the equation °R = °F + 459.67. The freezing point of water occurs at 491.67 °R, whereas its boiling point occurs at 671.67 °R.
The zero point of the Rankine scale matches that of the Kelvin scale, and the two scales are related by the equation °R = 1.8 × K. In certain fields of engineering, such as aerospace engineering, the Rankine scale is often preferred over the Kelvin scale with respect to absolute temperature.