Thermal radiation
(Redirected from Black body radiation)
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Thermal radiation
- in the way that physics uses it refers to "if it is above 0 Kelvin then it emits some electromagnetism"
- in an everyday sense we mostly think about the heat component
Incandescence is basically the same thing -- but zoomed in, caring only about the human-visible-light range of that EM emission
- usually with a temperature between 500K (below which you don't see much) and 15000K (some xenon lamps? Practically the ~6000K sun is what we see the most)
In the context of lighting,
- incandescent lightbulbs are wires that glow when given mains voltage, and continue glowing for a while.
- it's mainly contrasted with luminescence, which is roughly the "light for any other reason" category (and contains a handful of specific reasons).
Black-body radiation is also basically the same thing, or perhaps "thermal radiation's real-world math becomes easier if we add some assumptions like that it's not really interacting in other ways"
- e.g. assuming a uniform temperature
- e.g. assuming a uniform absorber of energy
- (which also helps it have a smooth spectrum.)
- Black body radiation also hints at that we might be describing things out in space. Because in that case, a body is isolated, and the way we see it is affected largely by heat.
If you wanted a "all things that happen at high temperature" view, there are some further things to list, such as thermionic emission.