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richardz03
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I read in some place that the mirror be it 100 per cent reflective, will also absorb if a light strikes to it. Is it true? what does it absorbs?
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Absorption of light in a mirror
- Thread starter richardz03
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In summary, mirrors are not 100% reflective and will absorb some amount of light, depending on the material they are made of. Different types of mirrors are designed to reflect different wavelengths of light, with aluminum being most reflective in the visible range and gold and silver being more reflective in the near-infrared range. The color of a mirror's reflection can also reveal its imperfections in reflecting different wavelengths.
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Drakkith
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No mirror is 100% reflective, so yes, some amount of light will be absorbed no matter what. A perfectly reflective mirror would, by definition, reflect 100% of the light and absorb none. But these do not exist.
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richardz03
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Drakkith said:
Ok but what does it absorbs? does it absorbs all the color a little bit or something else happens
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richardz03 said:
This doesn't quite make any sense, does it? If it is 100% reflective, then there is no absorption.
What exactly are you asking here? Are you asking on what happened to the light that is not reflected in a typical mirror? Or are you asking for something else?
Zz.
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Drakkith
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It will absorb a little bit of all the wavelengths. Mirrors can be made from many different materials to enhance their reflectivity of certain parts of the EM spectrum. For example, mirrors designed to reflect near-infrared light are typically made of gold because it reflects a larger portion of near IR light than most other kinds of mirrors. Aluminum is typically used to make visible light mirrors since it reflects a significant portion of visible light that falls on it, but will reflect less of other types of EM radiation such as UV or IR (it's also much cheaper than most alternative materials).
See the graph below, which comes from here: http://en.wikipedia.org/wiki/Reflectivity
As you can see, the amount of light reflected (measured by the Y-axis) changes depending on the wavelength and the type of mirror. Note that visible light has a wavelength between 400 nm to 700 nm. In this range the aluminum (Al) mirror reflects more light than the other two. Gold (Au) and silver (Ag) reflect more light in the near-IR range which is the right half of the graph.
See the graph below, which comes from here: http://en.wikipedia.org/wiki/Reflectivity
As you can see, the amount of light reflected (measured by the Y-axis) changes depending on the wavelength and the type of mirror. Note that visible light has a wavelength between 400 nm to 700 nm. In this range the aluminum (Al) mirror reflects more light than the other two. Gold (Au) and silver (Ag) reflect more light in the near-IR range which is the right half of the graph.
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Drakkith
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Just FYI, posts from another thread have been merged into this one.
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mfb
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Aluminium also reflects different wavelengths more evenly, so the reflections appear in the same colors as the original.Drakkith said:
As seen from the side, mirrors often look greenish, revealing that they are not perfect mirrors but absorb different wavelengths a bit differently.
1. What causes light to be absorbed in a mirror?
Light is absorbed in a mirror due to the electrons in the mirror's surface material. When light hits the mirror, the electrons in the material are excited, absorbing the energy of the light and converting it into heat energy.
2. Is all light absorbed in a mirror?
No, not all light is absorbed in a mirror. A small amount of light is reflected off the mirror's surface and the remaining light is absorbed by the material. The amount of light that is absorbed depends on the material and the wavelength of the light.
3. How does the angle of incidence affect the absorption of light in a mirror?
The angle of incidence, or the angle at which the light hits the mirror, does not have a direct effect on the absorption of light. However, it does affect the amount of light that is reflected and the angle at which it is reflected off the mirror's surface.
4. What factors affect the absorption of light in a mirror?
The absorption of light in a mirror is affected by the material of the mirror, the wavelength of the light, and the angle at which the light hits the mirror. Different materials and wavelengths of light will have varying levels of absorption in a mirror.
5. Can the absorption of light in a mirror be controlled?
Yes, the absorption of light in a mirror can be controlled by using different materials or coatings on the mirror's surface. By selecting a material with a specific absorption spectrum, the amount of light absorbed in the mirror can be adjusted.
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