Temperature
A convenient operational definition of temperature is that it is a measure of the average translational kinetic energy associated with the disordered microscopic motion of atoms and molecules.[1]
Temperature is expressed in degrees (symbol: ° ). There are two units of temperature in common use - Celsius (°C) and Fahrenheit (°F). Both make reference to the freezing and boiling points of pure water at normal atmospheric pressure.
Celsius (sometimes known as centigrade) sets the freezing point at 0 degrees (°C) and the boiling point at 100 degrees (100°C).
Fahrenheit sets the freezing point at 32 degrees (32°F) and the boiling point at 212 degrees (212°F).
Conversion of Fahrenheit to Celsius: °C = ( °F - 32 ) x 5 ÷ 9
Conversion of Celsius to Fahrenheit: °F = ( °C x 9 ÷ 5 ) + 32
Universally Celsius is the predominant system but Fahrenheit still holds sway in the USA.
An alternative scale is used in scientific circles. This is based on the value of a Celsius degree and is expressed as degrees Kelvin (°K) after the famous Irish-born physicist. The Kelvin scale sets 0° as the coldest possible temperature in the universe, where an object has no thermal energy, this is known as absolute zero and equates to -273.15°C or -459.67°F.