Dispersion and the electromagnetic spectrum

Learning objectives

Describe the dispersion of white light by a glass prism into the visible spectrum from red to violet, and at Extended know that monochromatic light has a single frequency

List the regions of the electromagnetic spectrum in order of frequency and wavelength, and know that all electromagnetic waves travel at the same high speed in a vacuum, which at Extended is 3.0 × 10⁸ m/s

Describe typical uses of radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma rays

Describe the harmful effects of excessive exposure to microwaves, infrared, ultraviolet, X-rays and gamma rays

Know that communication with satellites is mainly by microwaves and, at Extended, explain why microwaves are used for mobile phones, wireless internet and satellite links, why radio waves are used for Bluetooth and why optical fibres carrying light or infrared are used for cable TV and broadband, and compare analogue and digital signals and the advantages of digital transmission