science @lemmy.world m3t00🌎 @lemmy.world 10mo ago

In a surprising finding, light can make water evaporate without heat

news.mit.edu In a surprising finding, light can make water evaporate without heat

At the interface of water and air, light can, in certain conditions, bring about evaporation without the need for heat, according to an MIT study.

37 comments

Uh, I'm surprised.

I learned this in school more than a decade ago.

Did my teacher accidentally lied the truth?
- Light is energy. This isn't surprising to me at all.
  
  The energy transfer to evaporate water is the heat. This is specifically without heat.
  
  They proved more water was evaporated than the heat applied to the water.
  
  The theory being the light knocks away water particles at the surface of the water without heating them.
  
  Yeah that's the part that confuses me....how does one transfer energy to something without generating any heat?
Okay, this study has absolutely fascinated me. Tried to find the full study but failed, but Gang Chen (MIT professor, primary author) has a 40 minute symposium about it. Piped bot incoming, hopefully: https://m.youtube.com/watch?v=B1PbNTYU0GQ
- I like pounding YouTube on firefox with full ad-blocks engaged. hehe funny how nobody noticed. light is a range of frequencies so I'd expect best results at some harmonic frequencies.
green is best
- seems like harmonic frequencies should be interesting. I'm forgetting some facts but how does microwave line up with green light. with respect to harmonics. thought MIT didn't use clickbait headlines. https://duckduckgo.com/?q=green+light+frequencies+chart+microwave+harmonic+series
  
  ps. be nice
is this analogous to the photoelectric effect?
- photoelectric effect?
  
  looks similar. pe frees electrons while this experiment frees h2o molecules. they didn't really speculate on the exact mechanism. only something to do with the gel medium

37 comments