Why do objects glow red/white when heated?
In: Physics
That’s thermal radiation. All matter emit electromagnetic radiation (photon) depending on their temperature. The higher the temperature the smaller the wavelength of the radiation. So most of the stuff around you, including you, is in a temperature range that emit in infrared, so you don’t see it unless you look with an infrared camera. That’s how an infrared camera work, it detect the wavelength emitted by object, so if the wavelength is smaller it’s hotter, if the wavelength is bigger the object is colder. If the emit if hot like the heating element of your oven, then it emit in infrared, a little bit hotter like a fire and you will see it’s yellow in the middle where it’s hotter, but get orange and then red as you get further away from the source of the fire where it’s less hot.
You can see here the path of the thermal radiation and the color it will emit.
[https://en.wikipedia.org/wiki/Planckian_locus#/media/File:PlanckianLocus.png](https://en.wikipedia.org/wiki/Planckian_locus#/media/File:PlanckianLocus.png)
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