The SI base unit of thermodynamic temperature (equivalent in size to the degree Celsius), first introduced as the unit used in the Kelvin scale.
The kelvin was formerly defined by specifying the triple point of water as exactly 273.16 kelvins. In 2019 it was redefined in terms of the Boltzmann constant‘Liquid helium will cool the gyroscopes to 1.8 kelvins.’
- ‘During typical sonoluminescence experiments, spectral emission temperatures range up to tens of thousands of kelvins, and the rapidly imploding bubble walls can generate internal shock waves under certain conditions.’
- ‘To the scientists' surprise, tests showed that the resulting compound is a superconductor at cryogenic temperatures below 18.5 kelvins.’
- ‘The temperature of the lava, about 1,500 kelvins, is similar to that of the hottest volcanoes on Earth.’
- ‘Astronomers haven't been able to explain why the center of Perseus and other galaxy clusters are as hot as 50 million kelvins, even though the gas there radiates energy away and should therefore be cold.’
Late 19th century named after Lord Kelvin (see Kelvin, 1st Baron).