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quantum123
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Why does glass not permit long wavelength infrared to pass through?
can give me an idea about the properties of fused silicaZapperZ said:Certain glass (fused silica) can!
You might want to start by reading the FAQ in the General Physics forum. The entry on photon speed through a solid might be relevant.
Zz.
hycarbon said:can give me an idea about the properties of fused silica
Glass is a transparent material that is commonly used in windows and lenses. However, it does not allow long wavelength infrared (IR) radiation to pass through because its molecules are tightly packed and do not have the ability to vibrate at the same frequency as long wavelength IR radiation. This means that the energy from long wavelength IR radiation cannot be absorbed by glass, and therefore, it cannot pass through.
The structure of glass is made up of tightly packed molecules that are arranged in a regular pattern. This structure is what allows glass to be transparent to visible light, but it also means that the molecules are not able to absorb the energy from long wavelength IR radiation. This is because long wavelength IR radiation has a lower frequency than visible light, and the molecules in glass are not able to vibrate at such a low frequency.
No, not all types of glass are created equal when it comes to transmitting long wavelength IR radiation. Some types of glass, such as borosilicate glass, have a higher percentage of silica and are able to transmit longer wavelength IR radiation. However, even in these cases, the transmission is limited and not all long wavelength IR radiation will be able to pass through.
Long wavelength IR radiation is a form of heat energy that is emitted by objects with a temperature above absolute zero. If glass were to allow long wavelength IR radiation to pass through, it would result in a greenhouse effect, trapping the heat inside buildings and causing them to become uncomfortably warm. By blocking long wavelength IR radiation, glass helps to regulate the temperature inside buildings and reduces the need for excessive air conditioning.
Yes, there are ways to modify the structure of glass to make it more transparent to long wavelength IR radiation. One way is to incorporate certain elements, such as fluorine or germanium, into the glass composition. Another method is to use special coatings on the glass surface that are designed to selectively transmit long wavelength IR radiation. However, these solutions are often more expensive and may not be suitable for all applications.