Infra red radiation

Infra red radiation is part of the electromagnetic spectrum and has wavelengths between 0.007 mm and 0.001 mm (0.7 and 10 micrometres).

The popular name for infrared radiation is heat radiation. All objects give off infrared radiation, the hotter the object the more infrared radiation they emit and the shorter wavelength this radiation has.

Some parts of the human body are hotter than others and so give off more infrared radiation.

See: Wavelength and temperature

Exposure to high levels of infra red radiation can cause skin burns.

Uses of infrared radiation:

(a) physiotherapy for treating muscle strains

(b) night sights for use by the police, the military and by firemen when 'looking' for people trapped in smoke or ruins

(c) in medical scans to reveal unusually hot parts of the body that might be due to damage or illness.

(d) the infrared radiation give off by a poorly made join in power cables Using a camera sensitive to infrared radiation these places can be detected and then repaired. This reduces the energy wasted in electricity transmission across the country

(e) remote controllers for TV, radio and CD players send out an infrared beam to change channel, alter the volume etc.
You can also get a mouse that communicates with your computer using an infrared signal