I've heard that clear things such as the gaseous components of the atmosphere or water reflect no light, and that is why they are clear. I've also heard that black things such as asphalt are such because they reflect no light. What is the physical reason for these things to reflect no light yet be totally opposite, such as black and clear? How can something be black or clear but have the same property of absorbing all visible light?
[Physics] Clear vs black in terms of light reflection
opticsreflectionvisible-light
Best Answer
There is something you should think about and then hopefully things become clearer for you:
The athmosphere is only "clear" in a rather narrow region of the electromagnetic spectrum (see the nice graphic on the wikpedia page). For most wavelengths, our air is unclear and little of the incident light reaches earth's surface.
Another useful example here is glass. Glass transmitts visible light, as you can see everyday. BUT: Glass does not allow ultraviolet (or infrared) radiation to pass through. This leads to two effects if you get cought in a summer traffic jam:
So, a black object absorbs all visible light, but might be translucent (or at least not completely obstructive) to other wavelengths.