Värmestrålning

Värmestrålning is the emission of electromagnetic waves from all matter that has a temperature greater than absolute zero. This process is also known as infrared radiation. The energy radiated is a result of the thermal motion of atoms and molecules within the object. As these particles vibrate and move, they emit energy in the form of photons. The intensity and wavelength distribution of this radiation depend on the object's temperature. Hotter objects emit more radiation and at shorter wavelengths, while cooler objects emit less radiation and at longer wavelengths.

This phenomenon is a fundamental mechanism of heat transfer, allowing energy to travel through a vacuum without the need for a medium. A prime example is the Sun's radiation reaching Earth, which travels across the vast emptiness of space. Objects on Earth also exchange heat through radiation. For instance, a warm stove will radiate heat to its surroundings, and a person standing near a fireplace will feel the warmth from the flames. The color and surface properties of an object, such as its emissivity and absorptivity, also play a role in how effectively it emits and absorbs thermal radiation. Dark, matte surfaces are generally good emitters and absorbers, while shiny, light-colored surfaces are poor emitters and good reflectors.