It seems like other electromagnetic waves have some special properties. Microwave can heat the water molecules, infrared is basically “heat waves”. UV have enough energy to damage DNA and harm a living things. X-rays and Gamma radiation can penetrate a lot of material and also damage DNA. But the visible part is just visible, or it have some other properties?
In: Physics
It is nothin special except that we can see it, Why we can see it is because tit is a quite narrow band that make up 42% of the energy of sunlight at ground level [https://sunwindsolar.com/wp-content/uploads/2013/06/SunWind-WEB-Solar-Radiation-Spectrum-V2.png](https://sunwindsolar.com/wp-content/uploads/2013/06/SunWind-WEB-Solar-Radiation-Spectrum-V2.png) The peek prightness of the sun is in the visible part of the spectrum. So if you what to pick a spectrum to se reflected light from the sun that is the optimal specrum.
That infrared are heat waves are misleading. Heat is just transfer of energy in a thermodynamic system. Everything emmit electromagnetic radiation and the frequency spectrum depend on the temperature. This is called thermal radiation. For object to release visible light this way then need to be around 500C (900F) to emit a fain red glow we can see. More visible light is emmited the warmer it get.
Even at temperature of 2000 K (1700C, 3100F) 99% of the energy is released in the infrared part of the spectrum. The sun is at 5772K and at temperature like that visible light start to be around half of the energy. I could not find exact number for outside the atmosphere.
We think of infrared light as heat because the heating effect it has on our body is the only way we can detect it. It is alos where most thermal radiation from object on earth are emitted. If you call it heat waves you should call the visible light from the sun heat waves too. It is emmited for the same reason, the sun is just warmer then most stuff on earth. Visible light heat you up just like inraded light, what is added is you eyes ability to see it.
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