## Temperature Scales

 Many devices have been invented to accurately measure temperature. It all started with the establishment of a temperature scale. This scale transformed the measurement of temperature into meaningful numbers. Fahrenheit Scale In the early years of the eighteenth century, Gabriel Fahrenheit (1686-1736) created the Fahrenheit scale. He set the freezing point of water at 32 degrees and the boiling point at 212 degrees. These two points formed the anchors for his scale. Celcius Scale Later in that century, around 1743, Anders Celsius (1701-1744) invented the Celsius scale. Using the same anchor points, he determined the freezing temperature for water to be 0 degree and the boiling temperature 100 degrees. The Celsius scale is known as a Universal System Unit. It is used throughout science and in most countries. Kelvin Scale There is a limit to how cold something can be. The Kelvin scale is designed to go to zero at this minimum temperature. At a temperature of Absolute Zero there is no motion and no heat. Absolute zero is where all atomic and molecular motion stops and is the lowest temperature possible. Absolute Zero occurs at 0 degrees Kelvin or -273.15 degrees Celsius or at -460 degrees Farenheit.

The relationships between the different temperature scales are:

oK = 273.15 + oC

oC = (5/9)*(oF-32)

oF = (9/5)*oC+32

 oF oC oK Water boils 212 100 373 Room Temperature 72 23 296 Water Freezes 32 0 273 Absolute Zero -460 -273 0