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View Full Version here: : UV, Gamma Ray, X-ray, Infrared and Radio rainbows.


seanliddelow
16-08-2009, 05:33 PM
Ive been wondering.... If visble light is a part of the electromagnetic spectrum and visble light can be reflected thourgh raindrops why cant radio, infrared and gamma rays light and other parts of the spectrum be reflected threw rain drops as well?:help:

sheeny
16-08-2009, 05:42 PM
UV and at least some IR probably are refracted and reflected into rainbows similar to visible light.

Gamma rays simply go straight through lenses undeflected, so rain drops are probably treated much the same. I think Xrays are probably pretty similar, they are high energy, and don't respond well to normal lenses.

At the long wavelength end, I think it all falls down when the wavelength becomes about equivalent to the droplet size. The water droplet has to be bigger than the wavelength of the EM radiation for the radiation to see it.

Al.

MrB
16-08-2009, 05:45 PM
IR definitely does, and Radio frequencies do too... weather radar is an example....

http://mirror.bom.gov.au/products/IDR123.loop.shtml

renormalised
16-08-2009, 06:44 PM
Weather radar is down in the microwave end of the spectrum, actually most radars are. That's why they're affected by the weather, and precisely why they're designed the way they are. They're reflected by the raindrops, not refracted (for the most part). Once the wavelength reaches the average drop size and larger, then the radio waves pass straight through the clouds and raindrops unhindered.

Near UV is refracted quite markedly by raindrops, more so than blue/violet light, but Far UV is refracted less so because of the higher energies involved. It's the same with IR, but because of the opposite characteristics of IR...the longer the wavelength, the less refracted it becomes.