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Short-wavelength infrared SWIR, IR-B DIN: 1.4–3 μm 100–214 THz 413–886 meV 2,070–966 K (1,797–693 °C) Water absorption increases significantly at 1,450 nm. The 1,530 to 1,560 nm range is the dominant spectral region for long-distance telecommunications (see transmission windows). Mid-wavelength infrared MWIR, IR-C DIN; MidIR. [22]
The higher energy (shortest wavelength) ranges of UV (called "vacuum UV") are absorbed by nitrogen and, at longer wavelengths, by simple diatomic oxygen in the air. Most of the UV in the mid-range of energy is blocked by the ozone layer, which absorbs strongly in the important 200–315 nm range, the lower energy part of which is too long for ...
A household infrared electric heater. An infrared heater or heat lamp is a heating appliance containing a high-temperature emitter that transfers energy to a cooler object through electromagnetic radiation. Depending on the temperature of the emitter, the wavelength of the peak of the infrared radiation ranges from 750 nm to 1 mm. No contact or ...
Infrared radiation in the spectral distribution of a black body is usually considered a form of heat, since it has an equivalent temperature and is associated with an entropy change per unit of thermal energy. However, "heat" is a technical term in physics and thermodynamics and is often confused with thermal energy.
The infrared portion of the electromagnetic spectrum is usually divided into three regions; the near-, mid- and far-infrared, named for their relation to the visible spectrum. The higher-energy near-IR, approximately 14,000–4,000 cm −1 (0.7–2.5 μm wavelength) can excite overtone or combination modes of molecular vibrations.
Vibrational transitions in which a molecule gains a quantum of vibrational energy. The fundamental transitions give rise to absorption in the mid-infrared in the regions around 1650 cm −1 (μ band, 6 μm) and 3500 cm −1 (so-called X band, 2.9 μm) Electronic transitions in which a molecule is promoted to an excited electronic state.
That's the heat index. Here's how it works. The temperature on a summer day may be in the 80s or 90s. So why does it feel so much hotter? That's the heat index. Here's how it works.
In a practical, room-temperature setting, humans lose considerable energy due to infrared thermal radiation in addition to that lost by conduction to air (aided by concurrent convection, or other air movement like drafts). The heat energy lost is partially regained by absorbing heat radiation from walls or other surroundings.