When light hits a surface, there are basically three things that can happen, and the amount each happens depends on the wavelength ("color") of the light, the two materials on either side of the surface, and a bunch of other factors:
Part of the light is reflected, let's call that part R
Part of the light is transmitted through the surface, let's call that T
Part of the light is absorbed, let's call that A
Since those are the only three things that can happen, R+T+A=100% (pretty much, anyway).
On a perfect mirror, nothing is absorbed, nothing is transmitted, and all the light is reflected, so T=0%, A=0%, R=100%.
On a perfectly black surface (like ultrablack or VantaBlack paint), (almost) all the light is absorbed, so T=0%, A=100%, R=0%.
On a perfectly clear window, nothing is absorbed, nothing is reflected, all is transmitted, so A=0%, R=0%, T=100%.
Now, there is no such thing as a perfect surface, so what actually happens is a mix of all three. Like if you look through your windows, most of the light is transmitted, but there is a small fraction that is reflected (you can see what's outside, but you can also see a faint reflection of yourself). There's also a bit that absorbs, but you don't see that.
So yes, every time light reflects, at least part of it is absorbed by the surface and part of it is transmitted, so the reflection is less than the amount of light that hit the surface (it's weaker).
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Whether the reflected light is all the same direction or in in all directions has to do with the roughness of the surface and how it interacts with the light. Something like a mirror reflects all (most) of the light in the same direction, which is why you can see an image in it. That's called a specular reflection. Something like a white wall reflects the light in a mix of random directions, which is called a diffuse reflection. These can be mixed too, like if you look at aluminum foil, where you can see a reflected image but it's a bit blurry. That's a mix of specular and diffuse reflection.
jrallen7 t1_j9u3npe wrote
Reply to eli5 how does light get reflected?does it get reflected in all directions or in the direction where it came?and does light gets weaker everytime it gets reflected i mean does the reflection gets weaker even time it also reflects? by Substantial-Drop-726
When light hits a surface, there are basically three things that can happen, and the amount each happens depends on the wavelength ("color") of the light, the two materials on either side of the surface, and a bunch of other factors:
Since those are the only three things that can happen, R+T+A=100% (pretty much, anyway).
On a perfect mirror, nothing is absorbed, nothing is transmitted, and all the light is reflected, so T=0%, A=0%, R=100%.
On a perfectly black surface (like ultrablack or VantaBlack paint), (almost) all the light is absorbed, so T=0%, A=100%, R=0%.
On a perfectly clear window, nothing is absorbed, nothing is reflected, all is transmitted, so A=0%, R=0%, T=100%.
Now, there is no such thing as a perfect surface, so what actually happens is a mix of all three. Like if you look through your windows, most of the light is transmitted, but there is a small fraction that is reflected (you can see what's outside, but you can also see a faint reflection of yourself). There's also a bit that absorbs, but you don't see that.
So yes, every time light reflects, at least part of it is absorbed by the surface and part of it is transmitted, so the reflection is less than the amount of light that hit the surface (it's weaker).
​
Whether the reflected light is all the same direction or in in all directions has to do with the roughness of the surface and how it interacts with the light. Something like a mirror reflects all (most) of the light in the same direction, which is why you can see an image in it. That's called a specular reflection. Something like a white wall reflects the light in a mix of random directions, which is called a diffuse reflection. These can be mixed too, like if you look at aluminum foil, where you can see a reflected image but it's a bit blurry. That's a mix of specular and diffuse reflection.