Why some materials reflect light more than others?

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Materials reflect light differently due to their surface properties and structure. Smooth, flat surfaces, like mirrors, provide clear reflections by allowing light waves to bounce back uniformly. In contrast, rough or textured surfaces scatter light waves, resulting in diffused reflections. For instance, a mirror coated with a granular substance, such as peanut butter, reflects light less effectively due to its uneven surface. The fundamental principle is that while all surfaces reflect light, the degree and clarity of that reflection depend on the surface's characteristics.
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why some materials reflect light more than others?
 
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http://en.wikipedia.org/wiki/Reflection_(physics)"

The first part of this article is very exact in the explanation that light waves will reflect off of every surface they come in contact with; however, unless a surface is perfectly or nearly perfectly reflective, the light waves will return as simply diffused reflections of the energy.

For example, say I have a mirror that is totally flat and absolutely reflective. When I look at it, I see the reflection of whatever light waves are hitting upon it -those are the incident waves. I am seeing the resultant or reflection waves. Now, if I take the same mirror and coat it with peanut butter, I have a much less reflective surface. The light waves hitting it are still the same, however they are now being tossed and mixed about because the surface is granular and no longer flat. The energy (light) is still reflecting off of it, just not in the same clear manner that the original mirror reflected it.
 
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