Kelvin
The SI base unit of thermodynamic temperature. 0 K is absolute zero.
Definition
The kelvin (K) is the SI base unit of thermodynamic temperature. Zero kelvin (0 K) is absolute zero — the lowest possible temperature, where all thermal motion ceases. The kelvin scale has the same increment size as the Celsius scale: a difference of 1 K equals a difference of 1 °C.
Formula
K = °C + 273.15
Examples
- Water freezes at 273.15 K (0 °C).
- The surface of the Sun is about 5,778 K.
- The cosmic microwave background temperature is 2.725 K.