What is the quantity of 4KK?

4 kK is 4kk. Kelvin is a thermodynamic temperature scale or absolute temperature scale, and it is the degree-day in the international system of units. Kelvin temperature is often expressed by the symbol k, and its unit is open.

Kelvin is usually used to measure the color temperature of a light source. The color temperature is based on the principle that the color of the light emitted by the black body depends on the temperature of the radiator. The blackbody with temperature below 4000K is light red, and the blackbody with temperature above 7500K is light blue. Color temperature is very important in the field of projection and photography, and the color temperature around 5600K needs to match the "daylight" film.

In the field of astronomy, the spectra of stars and their positions in the Herotto diagram depend in part on their surface temperatures, which are called effective temperatures. For example, the effective temperature of the solar photosphere is 5778K K.

Extended data:

In blackbody radiation, the color of light changes with the change of temperature, and the blackbody presents a gradual change process from red-orange-red-yellow-yellow-white-white-blue-white. When the color of light emitted by a light source looks the same as the color of light emitted by a blackbody at a certain temperature, the temperature of the blackbody is called the color temperature of the light source.

The higher the temperature of the "black body", the more blue components and the less red components in the spectrum. For example, the light color of incandescent lamp is warm white, and its color temperature is expressed as 2700K, while the color temperature of fluorescent lamp is expressed as 6000 K.

The color of light emitted by some discharge light sources is not exactly the same as that emitted by blackbody at various temperatures. So in this case, the concept of "correlated color temperature" is used. When the color of the light emitted by the light source is closest to the color of the light emitted by a blackbody at a certain temperature, the temperature of the blackbody is called the correlated color temperature of the light source.

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