blackbody

blackbody
/blak"bod"ee/, n., pl. blackbodies. Physics.
a hypothetical body that absorbs without reflection all of the electromagnetic radiation incident on its surface. Also called perfect radiator.
[1700-10]

* * *

Theoretical surface that absorbs all radiant energy that falls on it, and radiates electromagnetic energy at all frequencies, from radio waves to gamma rays, with an intensity distribution dependent on its temperature.

Because all visible light falling on such a surface is absorbed without reflection, the surface will appear black as long as its temperature is such that its emission peak is not in the visible portion of the spectrum. See also absorption.

* * *

      in physics, a surface that absorbs all radiant energy falling on it. The term arises because incident visible light will be absorbed rather than reflected, and therefore the surface will appear black. The concept of such a perfect absorber of energy is extremely useful in the study of radiation phenomena.

      The best practical blackbody is a small hole in a box with a blackened interior, because practically none of the radiation entering such a hole could escape again, and it would be absorbed inside. A surface covered with lampblack will absorb about 97 percent of the incident light and, for most purposes, can be considered a blackbody. Polished metal surfaces, on the other hand, absorb only about 6 percent of the incident radiation, reflecting the rest.

* * *


Universalium. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • blackbody — [blak′bäd′ē] n. an ideal surface or body that can absorb completely all the radiation striking it …   English World dictionary

  • blackbody — a body with a surface emissivity of 1. Such a body will emit all of the thermal radiation it can (as described by theory), and will absorb 100% of the thermal radiation striking it. Most physical objects have surface emissivities less than 1 and… …   Mechanics glossary

  • Blackbody infrared radiative dissociation — Infobox chemical analysis name = Blackbody infrared radiative dissociation caption = acronym = BIRD classification =Mass spectrometry analytes = manufacturers = related = Infrared multiphoton dissociation Collision induced dissociation Electron… …   Wikipedia

  • blackbody temperature — juodojo kūno temperatūra statusas T sritis fizika atitikmenys: angl. blackbody temperature vok. schwarze Temperatur, f; Schwarzkörpertemperatur, f rus. температура абсолютно чёрного тела, f pranc. température du corps noir, f …   Fizikos terminų žodynas

  • blackbody radiation — noun the electromagnetic radiation that would be radiated from an ideal black body; the distribution of energy in the radiated spectrum of a black body depends only on temperature and is determined by Planck s radiation law • Syn: ↑black body… …   Useful english dictionary

  • blackbody — noun Date: 1710 an ideal body or surface that completely absorbs all radiant energy falling upon it with no reflection and that radiates at all frequencies with a spectral energy distribution dependent on its absolute temperature …   New Collegiate Dictionary

  • blackbody — noun a theoretical body, approximated by a hole in a hollow black sphere, that absorbs all incident electromagnetic radiation and reflects none; it has a characteristic emission …   Wiktionary

  • blackbody — Смотри абсолютно черное тело (а. ч. т.) …   Энциклопедический словарь по металлургии

  • blackbody — n. object which absorbs all wavelengths of electromagnetic radiation and is also the most efficient emitter of all wavelengths (Physics) …   English contemporary dictionary

  • Blackbody —   An ideal substance that absorbs all radiation falling on it, and reflecting nothing …   Energy terms

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”