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Sorry if this is the wrong place to post this but it seemed the most appropriate.

I read a riddle earlier today that mentioned something about shadows underwater and it got me thinking.. Would a shadow under water/ in the ocean technically be "wet"?

I understand that light isn't matter, but something.

I'm no good with physics myself but it's just a question that's been playing on my mind and would like to know if anyone has a logical answer to it?

Thank in advance!

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closed as unclear what you're asking by centralcharge, jinawee, Dilaton, BebopButUnsteady, Chris White Feb 14 '14 at 16:47

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question.If this question can be reworded to fit the rules in the help center, please edit the question.

I believe that you knew the answer to this question when you posted it (or at least that's the impression that I get, and that is why so many people have downvoted this). – Joshua Lamusga Jul 3 '14 at 19:50
Not that I can do anything, but can we stop closing questions for obviously untrue reasons? What the user is asking here is pretty obvious: can shadows underwater be considered 'wet'? In any case, the question is fairly clear. – Joshua Lamusga Jul 3 '14 at 19:54
Wow. 10 down votes. Seems a shame. If you are not clear on a concept, you really ought to be able to ask for clarification here. I give it +1 for originality. It would not have occurred to me to ask this. – mmesser314 Dec 27 '15 at 7:20
up vote 2 down vote accepted

The shadows that we can see with our naked eyes are simply areas less lightened than adjacent areas.

If you are talking about the wet sensation this is determinate by the contact of several liquid (not all mercury doesn't wet you..) with your skin. When you touch water or a water wetted material part of the water molecules are transfer to your hands (an hydrophilic material) and so to the receptor cells giving the sensation of wet, this sensation can be cause however in some case of parasthesias even if there are no liquid particles. In fact there are no "wet receptor" over your skin but the sensation is due to the elaboration of different stimuli from tactile, pressure and temperature receptor present in you skin. So something is not per se wet, but is an attribute we perceive.


... we could however say that "Wetting process" is caused by the presence of a thin liquid particles layer over a material. However saying that this area is wet has not much sense because shadow are not a material so can't be wet.


If for "shadow" you mean the material beneath a determinate area less lighted (so you are talking about the seabed less lighted) this depend from the chemistry of water and the chemistry of the seabed. Normal sand is hydrophilic (magic sand no, but seems there is no magic sand in the seabed normally :-) so is can be wetted. So in this case the sand is wet.

Quantistic approach

If for shadow area you mean an area you can't observe with photons so you question is: Can I determinate if an area of a material not irradiated by electromagnetic waves and submerge by water has a thin liquid water particles layer? so you want to determine it without using techniques that involves photons, because photons would invalidate your experiment. I think you can measure the temperature (with a very precise thermometer) of a box with a reproduction of a seabed after an adding of water in a dark room. A wetted material release a little little bit of heat when bond between water molecules are formed. Otherwise more simply you can put your hand beneath the sand before adding the water in complete darkness not so precise but I think is enough!

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Um.... a shadow is just an area where light doesn't reach, it isn't really made of anything, unless we go down to the light level, in which case wet doesn't mean anything.

So the question really is meaningless, but if I had to answer, I would say no, shadows underwater are not wet.

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And neither are they dry. – flonk Feb 14 '14 at 15:26

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