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davepl
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I have a (very basic) question on blackbody radiation (and no, its not my homework assignment... just trying to fill the gaps in some of the physics I missed 20 years ago when I -was- in school!).
As you heat an object, such as a block of metal, and as the temperature increases to higher energy levels, are light quanta emitted simultaneously at -all- the possible wavelength's predicted by Planck, or only at the shortest possible wavelength?
For example, if its "yellow hot", is it emitting red, orange, and yellow at the same time, or just yellow?
A second question, sort of tangential: why is there no "green hot"? The color spectra emitted after yellow seem to fill in all of the remaining color gaps, and go from yellow to white. I've read that the emissivity of metals makes it so they emit more easily in the blue wavelengths, but if that were the cause, I'd -expect- metal to look greensih when it was only "yellow hot". So you can see where I'm stuck :-)
Thanks!
Dave
As you heat an object, such as a block of metal, and as the temperature increases to higher energy levels, are light quanta emitted simultaneously at -all- the possible wavelength's predicted by Planck, or only at the shortest possible wavelength?
For example, if its "yellow hot", is it emitting red, orange, and yellow at the same time, or just yellow?
A second question, sort of tangential: why is there no "green hot"? The color spectra emitted after yellow seem to fill in all of the remaining color gaps, and go from yellow to white. I've read that the emissivity of metals makes it so they emit more easily in the blue wavelengths, but if that were the cause, I'd -expect- metal to look greensih when it was only "yellow hot". So you can see where I'm stuck :-)
Thanks!
Dave
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