Science Forums 2

[Turtle]

Originally Posted by Mercedes Benzene

Turtle, you posted a link earlier about disinfecting water using the sun. Here's a wiki page I found giving more info. Apparently UV-A can be effectively used to kill microbes, but it requires a long exposure and is aided by higher temperatures.

indeed. so the old question remains, does a 'magnifying' lens, of any material whatsoever, bend any range of UV radiation whatsoever, to a focus as they do visible light? i have asked 3 times & looked on my own 4 times & still have nada. no speculations thank you; just the physics phacts Mam.

now in light ( ) of your wiki and my original article, the new question is how significant a factor is the volume of water being treated with Sunlight to the amount of time necessary? which is to say will a larger bottle of PET plastic containing contaminated water take longer than a smaller bottle to sterilize when place out in the Sun? again, the physics please.

also, since the water is largely transparent, won't any particles, spores, protozoa and the like absorb the other light frequencies that do come to a focus? won't that fry them?

i may make a little experimental stand and try my hand at blazing some water drops. i have access to a 4 or 5 inch magnifying glass. ants be forewarned.