INCANDESCENCE is the emission of electromagnetic radiation (including visible light ) from a hot body as a result of its temperature. The term derives from the Latin verb incandescere, to glow white.
For a detailed discussion of the intensity and spectrum (color) of incandescence, see the article: thermal radiation .
* 1 Observation and use * 2 Figurative use * 3 See also * 4 References * 5 External links
OBSERVATION AND USE
Main article: Thermal radiation
In practice, virtually all solid or liquid substances start to glow around 798 K (525 °C) (977 ˚F), with a mildly dull red color, whether or not a chemical reaction takes place that produces light as a result of an exothermic process. This limit is called the Draper point . The incandescence does not vanish below that temperature, but it is too weak in the visible spectrum to be perceivable.
At higher temperatures, the substance becomes brighter and its color changes from red towards white and finally blue.
More efficient light sources, such as fluorescent lamps and LEDs , do not function by incandescence.
The word incandescent is also used figuratively to describe a person who is so angry that they are imagined to glow or burn red hot or white hot.
Dionysius Lardner (1833). Treatise on Heat. Longman, Rees,
Orme, Brown, Green & Longman. The state in which a heated body,
naturally incapable of emitting light, becomes luminous, is called a
state of incandescence.
* ^ John E. Bowman (1856). An Introduction to Practical Chemistry,
Including Analysis (Second American ed.). Philadelphia: Blanchard and
* ^ William Elgin Wickenden (1910). Illumination and Photometry.
* ^ Example 1:'...the stadium positively crackled with the
incandescent anger of anguished supporters.' Mark Wilson, 'Rangers 1