Are light and heat always required together? Is it possible to have light without heat?
In: Physics
You can generate light without much waste heat with something like an LED. However all light contains energy and when absorbed it will increase the temperature.
Heat is a requirement of the universe. Everything that exists must be at a temperature above absolute zero.
Heat is not s thin in it self, it is energy transfer in a thermodynamic system.
What you might call heat is infare radiation, ie light in a lower frequency then we can see. It transfer energy to you when it hit you just like visible light.
All matter warmer then absolutely zero will emit thermal radiation, that is electromagnetic radiation that includes or and visible light. Which wavelengths are emmited depen on the temperature
If you have light from something that hits something you have energy transfer ie heat. Even if the light is just emmited and travel out into space you transfer energy ie heat.
So you can’t have light and not heat because light transmitts energy
You can have visible light without IR light, a led will primary radiate är a narrow wavelength band. But there is losses that heat up the light source and it emmit thermal radiation, at temperatures we have in earth that will include it radiation
I think the most efficient light-heat in nature is the lightning bug. Very visible light with negligible heat. Phosphorescence may also be one
Yes, this is always happening you just can’t always perceive the light as it is in frequencies outside of the range of your perception.
Heat is atomic motion which is a form of energy. Some of the energy is shed from the electron shells as photons. The amount of energy lost translates to the frequency of the light. Hot enough objects emit light in frequencies you can see.
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