Black body Radiation
What gives rise to a continuous spectrum? Imagine heating a solid steel sphere with a blowtorch. When you remove the torch you can feel the heat being re-radiated by the sphere.
Black Body Radiation
Radiation emitted by a hypothetical perfect radiator. The spectrum is continuous, and the wavelength of maximum emission depends only on the body's temperature.
Black Dwarf ...
Black body radiation--light or other electromagnetic radiation emitted due to heat by a solid, liquid or dense gas, with no color of its own (hence "black").
BLACK BODY RADIATION
Black body radiation is the radiation produced by a black body.
Black body radiation is sort of a reverse of what happens when you are sunbathing and you absorb heat energy from the rays of the sun. The hotter an object is, the more it will emit heat radiation of its own.
For black body radiation, in equilibrium with the exposed surface, the energy density is, in accordance with the Stefan-Boltzmann law, equal to σT4/3c; in which σ is the Stefan-Boltzmann constant, c is the speed of light, ...
For black body radiation the rate of energy radiation per unit area per unit wavelength range at constant kelvin temperature T1 can be plotted against wavelength. It is found that there is a peak at wavelength 1.
[1.2] MAX PLANCK & BLACK BODY RADIATION
[1.3] EINSTEIN & THE PHOTOELECTRIC EFFECT
[1.4] THE DISCOVERY OF RADIOACTIVITY ...
thermal radiation (black body radiation)
incandescent light bulbs
sunlight
glowing solid particles in flames (see fire) ...
Because all objects emit black body radiation, a thermometer in a vacuum away from thermally radiating sources will radiate away its own thermal energy; decreasing in temperature indefinitely until it reaches the zero-point energy limit.
These coronal hot spots give off X-rays in the form of black body radiation. A black body is an object that is hot and radiates some of its energy away in the form of different types of light.
For a warm and dense (non-gaseous substance in high pressure) object (such as a star or a piece of metal), it will radiate light (electromagnetic wave) and the spectrum follows what we call a black body radiation.
Steven Hawking demonstrated that all black holes should emit black body radiation. This radiation is actually a loss of mass.
[37] The two "dark clouds" he was alluding to were the unsatisfactory explanations that the physics of the time could give for two phenomena: the Michelson-Morley experiment and black body radiation.
When an object reaches a temperature where it becomes too hot to radiate black body radiation in the visible wavelengths, it will shine in ultraviolet wavelengths. Hotter still, x-rays, and finally gamma rays.
The black dwarf, or stellar remnant, subsequently cooled down such that it only emits black body radiation.
Heaviside's proposal, coupled with Planck's law of black body radiation, ...
As another example, thermal equilibrium implies that the photons in the early universe did not have some arbitrary distribution, but were instead described by the intensity and spectrum of black body radiation. [G97] ...
 See also: Temperature, Light, Energy, Time, Emission
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