Radiation - Wikipedia
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a material medium. [1][2] This includes: electromagnetic radiation consisting of photons, such as radio waves, microwaves, infrared, visible light, ultraviolet, x …
Emissivity and Final Temperature of a Black and White object
2016年3月28日 · The white body reflects all the incident radiation, so it's spectrum will be the same as that of the incoming sunlight. The black body, however, absorbs all incoming sunlight and emits blackbody radiation .
What is white body in radiation? - Physics Network
2023年5月11日 · A white body is one for which all incident radiation is reflected uniformly in all directions: τ = 0, α = 0, and ρ = 1. For a black body, τ = 0, α = 1, and ρ
Laws of Thermal Radiation - SpringerLink
2020年6月19日 · A body with reflectivity of unity will reflect the whole of the incident radiation and is termed a white body. When the reflection from a body obeys the laws of geometrical optics (angle of the reflected beam with normal equals the angle of the incident beam with the normal) the body is called smooth or specular .
6.2: Blackbody Radiation - Physics LibreTexts
Therefore, a good absorber of radiation (any object that absorbs radiation) is also a good emitter. A perfect absorber absorbs all electromagnetic radiation incident on it; such an object is called a blackbody. Figure 6.2.1 6.2. 1: A blackbody is physically realized by a small hole in the wall of a cavity radiator.
14.7: Radiation - Physics LibreTexts
In contrast, white is a poor absorber and is also a poor radiator. A white object reflects all radiation, like a mirror. (A perfect, polished white surface is mirror-like in appearance, and a crushed mirror looks white.)
Understanding Classical Gray Body Radiation Theory
2018年11月1日 · A gray body is an imperfect black body; i.e., a physical object that partially absorbs incident electromagnetic radiation. The ratio of a gray body’s thermal radiation to a black body’s thermal radiation at the same temperature is called the emissivity of the gray body.
What is the Difference Between Black Body and Grey Body
2023年12月1日 · A black body is an idealized physical body that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence. A grey body, on the other hand, is an object or substance that partially absorbs and partially reflects or transmits electromagnetic radiation.
Blackbody radiation | Definition & Facts | Britannica
2024年9月14日 · blackbody radiation, energy radiated by any object or system that absorbs all incident radiation. The term usually refers to the spectrum of light emitted by any heated object; common examples include the heating element of a toaster and the filament of a light bulb.
Blackbody | Definition, Color, & Facts | Britannica
Blackbody, in physics, a surface that absorbs all radiant energy falling on it. The term arises because incident visible light will be absorbed, not reflected, and therefore the surface will appear black. The concept of such a perfect absorber of energy is extremely useful, as can be seen in Planck’s radiation law.