Changes

The '''infrared''' portion of the [[electromagnetic spectrum]] consists of light which has a longer wavelength than the human eye can detect.  

The '''infrared''' portion of the [[electromagnetic spectrum]] consists of light which has a longer wavelength than the human eye can detect (that is, above 800 nm). ''Infra'', meaning ''below'' in latin, is used because the [[frequency|frequencies]] of the infrared are below those of the red colour. Infrared is used in communications by [[optical fiber]]s (wavelength 1550 nm), in lamps to keep food warm, in military detection equipment (for example because the heat of the human body can be perceived as an infrared radiation around 10 µms).

 

Infrared light is used in lamps to keep food warm.

==See also==

==See also==

*[[microwaves]]

*[[microwaves]]

[[category:physics]]

[[category:physics]]