Do all bodies radiate at all frequencies?

AI Thread Summary
All bodies above absolute zero emit energy, described by the Stefan-Boltzmann law, P = AeσT^4. To determine the frequency of emitted power based on temperature, Planck's radiation law provides the frequency distribution. As temperature increases, the variety of emitted frequencies also increases, which is crucial for making gases glow visibly. Gases do not behave as perfect black bodies and emit radiation in specific spectral bands. Understanding these principles is essential for calculating the heat required for a gas to emit visible light.
zeromodz
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I know that all bodies with a temperature above absolute zero radiate energy away as the following.

P = AeσT^4

However, I wanted to know how you could find the frequency of the power being emitted just by knowing the temperature. For example, how would I find out how much heat I need to put in a specific gas in order for it to radiate visible light (make it glow). I know that the hotter you get it, the more variety of frequencies you get.
 
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zeromodz said:
I know that all bodies with a temperature above absolute zero radiate energy away as the following.

P = AeσT^4

However, I wanted to know how you could find the frequency of the power being emitted just by knowing the temperature. For example, how would I find out how much heat I need to put in a specific gas in order for it to radiate visible light (make it glow). I know that the hotter you get it, the more variety of frequencies you get.
The frequency distribution as a function of temperature is given by Planck's radiation law. See for example: http://en.wikipedia.org/wiki/Planck%27s_law"

AM
 
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