CP5 Using the long wavelengths

Slide 1

USING THE LONG WAVELENGTHS

• The uses for the waves in different parts of the electromagnetic spectrum depend on their wavelength

Visible Light

• Visible light is the part of the electromagnetic spectrum that our eyes detect. Light bulbs are designed to emit visible light, while cameras detect it and record images.

Infrared

• Infrared radiation can be used for communication at short ranges, such as between computers in the same room or from a TV to its remote control unit. The information sent along optical fibres is also sent using infrared radiation.
• A grill or toaster transfers energy to food by infrared radiation. the good absorbs the radiation and heats up. Thermal images show the amount of infrared radiation given off by different objects.
• Security systems often have sensors that can detect infrared radiation emitted by intruders. Some buildings are fitted with systems or infrared beams and detectors - someone walking through one of these beams breaks it and sets it off.