Earlier quoted context omitted.
So a watched kettle might boil faster?
You emmit green light from your eyes?
If you have green eyes, yes.
Light can make water evaporate without heat
151–160 of 198 posts
Re: Light can make water evaporate without heat
#152> The researchers found that the effect varied with color and peaked at a particular wavelength of green light. I wonder if this affects photosynthesis in any way? IIRC plants are green because chlorophyll does not absorb that color. Maybe that’s partially because green light induces too much evaporation?
No. Plants reflect green to balance luminosity extremes.
Green is by far the most luminous color in the visible spectrum with dark purple being the least luminous. Plants that reflect purple absorb the most visible light and can produce the most sugars. Most plants must undergo a chemical transition to shift from production to dark mode and by choosing to reflect green maximum energy production is sacrificed for internal chemical stability.
Re: Light can make water evaporate without heat
#153Earlier quoted context omitted.
The sea is on the other side of a very carefully policed barrier.
Still, it's less of a challenge to pump water from your roots if you're in the sea. Did the earliest green plants even have roots?
> Did the earliest green plants even have roots?
No. Not even all land plants have roots.
Re: Light can make water evaporate without heat
#154Earlier quoted context omitted.
Sound would literally mean waves of kinetic energy hitting both the surface of the water and traveling inside it. Does that really count as "without heat"?
And what type of energy is light?
One which can get absorbed by a single molecule individually as opposed to sound which has to affect large groups of them, increasing movement / heat.
Re: Light can make water evaporate without heat
#155> The researchers found that the effect varied with color and peaked at a particular wavelength of green light. I wonder if this affects photosynthesis in any way? IIRC plants are green because chlorophyll does not absorb that color. Maybe that’s partially because green light induces too much evaporation?
Maybe, but evaporation is critical for plants. They don't have a heart to pump blood and supply nutrients, they have to rely on evaporation to move nutrients from the roots up
That’s a good point actually. I never thought about the fact that a tree is evaporating 100L a day without any heat. They must have figured this out.
Re: Light can make water evaporate without heat
#156Earlier quoted context omitted.
And what type of energy is light?
One which can get absorbed by a single molecule individually as opposed to sound which has to affect large groups of them, increasing movement / heat.
Sound is movement, it’s not a particle. It’s your way of sensing stuff smashing together by feeling the ripple that comes off it
Re: Light can make water evaporate without heat
#157Earlier quoted context omitted.
Maybe, but evaporation is critical for plants. They don't have a heart to pump blood and supply nutrients, they have to rely on evaporation to move nutrients from the roots up
That’s a good point actually. I never thought about the fact that a tree is evaporating 100L a day without any heat. They must have figured this out.
It still uses heat. Evaporation actually helps plants keep cool by using up the heat from sun that would otherwise heat the plant too much.
Re: Light can make water evaporate without heat
#158Earlier quoted context omitted.
Thermodynamics and evaporation are my day job and I think most other explanations here are missing the point. Evaporation normally occurs when individual water molecules have enough thermal energy to break their intermolecular bonds, leaving the bulk liquid and entering the air. In this case, they found strong evidence that water molecules were being removed in groups of several water molecules. Because intermolecula…
> I'm not really sure whether to even call it evaporation I can't help but think of ultrasonic humidifiers/misters, which use vibration to do evaporation-adjacent kinds of things. I also wonder if specific wavelengths of light are involved (sort of how 2.4ghz microwaves work on water)
Cue “burning” salt water video:
https://youtu.be/e8utkoK2DhA?si=t2cvuu4V-hFKFjM8
I’m still blown away that radio frequencies can dissociate hydrogen without an electrode. I haven’t read a good explanation of the phenomenon.
Re: Light can make water evaporate without heat
#159I must be missing something. My ice cubes in my freezer evaporate with no light and no heat. My understanding of the situation was the surrounding air was pulling off moisture because of some sort of osmosis effect. So why is this news?
This is news because we thought that light by itself doesn't actually affect water evaporation. We found a new mechanism for evaporation, that's exciting, scientists love when they find something that allows them to find out even more about how things work.
Re: Light can make water evaporate without heat
#160> The researchers found that the effect varied with color and peaked at a particular wavelength of green light. I wonder if this affects photosynthesis in any way? IIRC plants are green because chlorophyll does not absorb that color. Maybe that’s partially because green light induces too much evaporation?
No. Plants reflect green to balance luminosity extremes. Green is by far the most luminous color in the visible spectrum with dark purple being the least luminous. Plants that reflect purple absorb the most visible light and can produce the most sugars. Most plants must undergo a chemical transition to shift from production to dark mode and by choosing to reflect green maximum energy production is sacrificed for inte…
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