why are liquids reflective?

Sebastian

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I've been wondering for a long time why liquids reflect light, but when they dry they are no longer reflective. For example, when you write with a pen, the ink is shiny when it first comes from the pen, but when you let it sit and dry, the ink is no longer reflective. Anyone know why this is?
 
Well, being a somewhat nerd I can kind of help. When the liquid is wet it is reflective because of the fact that it has a different density to the air above/around it. I suppose this would work best in a glob of ink or something. Anyway, when the light enters the liquid from the less dense air, it's (possesive) path is altered to an extent, due to the more dense liquid. Because of this, the light would then travel outside the ink at an angle and appear shiny. As for the drying thing, maybe it's just that. Because it isn't a liquid any more.

Hope that helped.
 
Liquids are reflective because they have the property Reflective set to 1. Noob.
 
Well, being a somewhat nerd I can kind of help. When the liquid is wet it is reflective because of the fact that it has a different density to the air above/around it. I suppose this would work best in a glob of ink or something. Anyway, when the light enters the liquid from the less dense air, it's (possesive) path is altered to an extent, due to the more dense liquid. Because of this, the light would then travel outside the ink at an angle and appear shiny. As for the drying thing, maybe it's just that. Because it isn't a liquid any more.

Hope that helped.

Would that reflect light or just refract it?

My guess (and this is a guess) would be that the surface of the liquid is very smooth because of forces between liquid molecules. Since they're cohesive there would be some surface tension which pulls the molecules into a shape with a smooth surface (as in, with a drop of water on wax paper, it balls up and gives a nice reflective round surface). This would also explain why polished metals are reflective even though they are not liquids.
 
Aww.. I thought you meant water... I knew that one.. I didn't think solid coloured liquids :( I coulda shown off me smarts!
 
Would that reflect light or just refract it?

My guess (and this is a guess) would be that the surface of the liquid is very smooth because of forces between liquid molecules. Since they're cohesive there would be some surface tension which pulls the molecules into a shape with a smooth surface (as in, with a drop of water on wax paper, it balls up and gives a nice reflective round surface). This would also explain why polished metals are reflective even though they are not liquids.

Yes. Dry ink does reflect light, but it is diffuse reflection. If not, how can you see there is ink?
 
Yes. Dry ink does reflect light, but it is diffuse reflection. If not, how can you see there is ink?

Well actually all matter be it liquid, solid, or gas reflects light to some extent otherwise we wouldn't see anything.:smoking:
 
Well, ask yourself why a mirror is reflective? It's reflective because its smooth surface bounces back light without diffusing it. Liquids have a smooth surface (because of surface tension?) so they reflect light back without diffusion. When it dries up, the surface is often no longer smooth (because it crystallizes or solid particles in the liquid remain while the liquid evaporates) so it diffuses light in all directions.
 
Apply to what? Everything that I've learned in Physics 1 & 2 cannot be applied to life, unless you worked with lasers and scalar pulses or something.

general knowledge = e-peen boast =D
 
It's total internal refraction I think, so technically there isn't any reflection taking place.

1244453535 said:
Apply to what? Everything that I've learned in Physics 1 & 2 cannot be applied to life, unless you worked with lasers and scalar pulses or something.

Physics can be applyed to almost everything, try throwing a ball at a wall at a angle, if you managed to catch it you used physics :p.
 
Physics can be applyed to almost everything, try throwing a ball at a wall at a angle, if you managed to catch it you used physics :p.
Yeah, but I didn't care.

omg, numbers learned scalar waves in school D:
 
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