Difference between revisions of "Temperature"
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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.<ref> http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/temper.html </ref> | 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.<ref> http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/temper.html </ref> | ||
| − | + | Temperature is expressed in degrees (symbol: ° ). There are two units of temperature in common use - [[Celsius degree|Celsius]] (°C) and [[Fahrenheit degree|Fahrenheit]] (°F). Both make reference to the freezing and boiling points of pure water at normal atmospheric pressure. | |
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| + | Celsius (sometimes known as centigrade) sets the freezing point at 0 degrees (°C) and the boiling point at 100 degrees (100°C).<br> | ||
| + | Fahrenheit sets the freezing point at 32 degrees (32°F) and the boiling point at 212 degrees (212°F).<br> | ||
| + | Conversion of Fahrenheit to Celsius: °C = ( °F - 32 ) x 5 ÷ 9<br> | ||
| + | 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. | ||
==References== | ==References== | ||
<references/> | <references/> | ||
[[category:physics]] | [[category:physics]] | ||
Revision as of 20:18, May 10, 2007
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.