Explaining the Sun's Effects on Rough Surfaces Covered in Water

AI Thread Summary
Rough surfaces appear darker in sunlight when covered with water due to the way light interacts with the water and the surface. The polarization of light and total internal reflection may play a role, as some light is reflected off the water's surface and some is absorbed by the denser medium. This effect is influenced by the angle of incidence and refraction, which affects how much light is scattered versus reflected. The presence of water reduces the scattering of light that would typically occur with a dry, rough surface. Overall, the combination of reflection and absorption leads to the darker appearance of these surfaces.
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Rough (not smooth) surfaces often appear to be darker in sunlight when they are covered by water.How can we explain this physical phenomen?
 
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I'm no expert in this by any means, but I suspect that it's due to polarization of the light coming back from the water.
 
Can it be total internal reflection.In this case light cannot go out from the liquid.
 
Not total, or you would see nothing at all. Honestly, though, wait for someone with appropriate knowledge to help you. I'm not qualified. I just guessed at the polarization because a very long time ago when I wore Polaroid sunglasses, a puddle on a sidewalk looked to be a couple of miles deep. Without the glasses, it was just a puddle.
 
First off you will have some of the light reflected off the surface so not all the light makes if through the water to the object.
Then some of the light is also reflected back into the water when it encounters the boundary again on its way out.
You will also have some of the light absorbed by the denser medium.

At least the would be my guess.

This would be true for both smooth and rough objects though.
Maybe it has to do with the angle of incidence and the angle of refraction.
 
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The effect has more to do with the fact that by coating the object with water, a good deal of light is reflected off the surface, instead of being scattered in random directions by the rough, dry surface.
 
I think it's easist first to watch a short vidio clip I find these videos very relaxing to watch .. I got to thinking is this being done in the most efficient way? The sand has to be suspended in the water to move it to the outlet ... The faster the water , the more turbulance and the sand stays suspended, so it seems to me the rule of thumb is the hose be aimed towards the outlet at all times .. Many times the workers hit the sand directly which will greatly reduce the water...
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