examples of black body which is not in black color
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Answer:
Does a black-body always appear black?
Galaxy Unpacked.
Does a black-body always appear black?
As Mark Barton has written, the answer is no. It does not always appear black. The name derives from the concept of a black-body as a theoretically ideal absorber of light (and other electromagnetic radiation). However, that also happens to make it a perfect emitter.
A ideal black-body at “room temperature” would indeed appear black, but if heated enough it would start to emit light. This is shown in graphs of “black-body radiation”. The point is that if a black-body is a perfect absorber of light, it’s also a perfect emitter of light, when hot enough.
Incidentally, at room temperature a black-body will be emitting infra-red radiation, but that’s invisible to our eyes without special detectors and so it appears black to us. A temperature of around 900 Kelvin is needed for a black-body to become visible to us by emitted radiation alone.
Incidentally, something that emits radiation that’s similar to a perfect black-body radiator doesn't actually have to be black (when cool). Most bodies behave quite like black-body radiators, irrespective of their (room temperature) colour.
This is a link about black-bodies, discussed in the context of astronomy. Some of the link will not work unless you have the right software, but that’s not too important. Also, the page has are a few minor grammatical errors, but it’s still quite a nice introduction to the idea of black-body radiation: