Question
Write a short note on Infrared waves.
✓
Answer
$\rightarrow $ IR $($ Infrared $)$ waves are produced by hot bodies and molecules.
$\rightarrow $I.R. waves are sometimes referred to as heat waves. This is because water molecules present in most materials readily absorb infrared waves. $($ many other molecules, for example, $CO_2, NH_3 $ also absorb infrared waves $)$ After absorption, their thermal motion increases, that is, they heat up and heat the surroundings.
$\rightarrow $ Range of wavelength from $7 \ mm$ to $700 \ nm.$
$\rightarrow $ Infrared lamps are used in physical therapy.
$\rightarrow $ Infrared radiation also plays an important role in maintaining the earth's warmth or average temperature through the greenhouse effect.
$\rightarrow $ I.R. detectors are used in Earth satellites, both for military purposes and to observe growth of crops.
$\rightarrow $ Electronic devices $($semiconductor $LEDs)$ also emit infrared and are widely used in remote switches of household electronic systems such as, $TV$ sets, Video recorders and hi-fi systems.
$\rightarrow $I.R. waves are sometimes referred to as heat waves. This is because water molecules present in most materials readily absorb infrared waves. $($ many other molecules, for example, $CO_2, NH_3 $ also absorb infrared waves $)$ After absorption, their thermal motion increases, that is, they heat up and heat the surroundings.
$\rightarrow $ Range of wavelength from $7 \ mm$ to $700 \ nm.$
$\rightarrow $ Infrared lamps are used in physical therapy.
$\rightarrow $ Infrared radiation also plays an important role in maintaining the earth's warmth or average temperature through the greenhouse effect.
$\rightarrow $ I.R. detectors are used in Earth satellites, both for military purposes and to observe growth of crops.
$\rightarrow $ Electronic devices $($semiconductor $LEDs)$ also emit infrared and are widely used in remote switches of household electronic systems such as, $TV$ sets, Video recorders and hi-fi systems.
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