Sun rays coming to Earth, carrying thermal energy (heat) through electromagnetic waves. Heat transfer is called radiation, which can take place in a vacuum. Radiation emitted by an object as a result of its temperature is called heat radiation. Obviously, every object is continuously emitting heat radiation in the form of electromagnetic waves. In fact, a cube of ice that we often see in everyday life also emit heat radiation energy, although with a very small fraction of this heat radiation in the visible light region.
In the laboratory, newly visible objects radiate heat if the temperature exceeds 1000 K. At this temperature the object started glowing red just like when we turn on an electric stove coil and color indicates the color red. When the temperature rose to 2000 K, the object will be fluorescent yellow or whitish like the fluorescent iron on the light bulb. So also the higher the temperature of the object will be more different colors are emitted. However, in the physical sciences, there is a hot body that emits thermal spectra with the same characters / universal. Black body (black body) is the name of the object. In physics itself, a black body is an object that absorbs all electromagnetic radiation that falls to the black body. No radiation can exit or reflected by the black body.
In the experiment, the object that most closely approximates a black body radiation is the radiation from a small hole in a cavity. Any light entering the hole close and this will be reflected and the energy absorbed by the walls of the cavity many times, regardless of wall material and the wavelength of incoming radiation (long wavelength smaller than the diameter entrance hole). This hole is the approach of a black body. Although his name black object, he should not really black because he also can transmit energy. The number and types of electromagnetic radiation emitted depends on the black body temperature. Black body with a temperature below 700 K almost all the energy emitted in the form of infrared waves, very little in the visible wavelengths. The higher the temperature, the more energy is emitted in the visible wavelength starts red, yellow, orange and white.
The higher the temperature when the cavity is heated, the more visible light can be seen. The observed waves could not be explained by classical electromagnetic theory and statistical mechanics. This theory predicts a high intensity at low wavelengths (ie high frequency). Theoretic Problem was solved by the Max Planck stated that electromagnetic radiation propagating in empty space is not continuous but propagate in the form of packages or often called a photon. While the term black body itself was first introduced by Gustav Robert Kirchoff in the year 1862 and the radiation that comes out / is emitted by a black body that is called blackbody radiation.
In the laboratory, newly visible objects radiate heat if the temperature exceeds 1000 K. At this temperature the object started glowing red just like when we turn on an electric stove coil and color indicates the color red. When the temperature rose to 2000 K, the object will be fluorescent yellow or whitish like the fluorescent iron on the light bulb. So also the higher the temperature of the object will be more different colors are emitted. However, in the physical sciences, there is a hot body that emits thermal spectra with the same characters / universal. Black body (black body) is the name of the object. In physics itself, a black body is an object that absorbs all electromagnetic radiation that falls to the black body. No radiation can exit or reflected by the black body.
In the experiment, the object that most closely approximates a black body radiation is the radiation from a small hole in a cavity. Any light entering the hole close and this will be reflected and the energy absorbed by the walls of the cavity many times, regardless of wall material and the wavelength of incoming radiation (long wavelength smaller than the diameter entrance hole). This hole is the approach of a black body. Although his name black object, he should not really black because he also can transmit energy. The number and types of electromagnetic radiation emitted depends on the black body temperature. Black body with a temperature below 700 K almost all the energy emitted in the form of infrared waves, very little in the visible wavelengths. The higher the temperature, the more energy is emitted in the visible wavelength starts red, yellow, orange and white.
The higher the temperature when the cavity is heated, the more visible light can be seen. The observed waves could not be explained by classical electromagnetic theory and statistical mechanics. This theory predicts a high intensity at low wavelengths (ie high frequency). Theoretic Problem was solved by the Max Planck stated that electromagnetic radiation propagating in empty space is not continuous but propagate in the form of packages or often called a photon. While the term black body itself was first introduced by Gustav Robert Kirchoff in the year 1862 and the radiation that comes out / is emitted by a black body that is called blackbody radiation.
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