Apply wave speed = frequency x wavelength to electromagnetic waves.

For electromagnetic waves, v = f? links the shared vacuum speed to the different frequencies and wavelengths across the spectrum. Students should use this relationship to explain why radio waves have long wavelengths and low frequencies while gamma rays have very short wavelengths and high frequencies. The calculation must keep wave speed in m/s, frequency in Hz and wavelength in metres. The important boundary is that electromagnetic waves all travel at the same speed in a vacuum, so spectrum position changes frequency and wavelength, not vacuum velocity. Within the subtopic Properties of electromagnetic waves in Electromagnetic waves, the explanation is anchored to electromagnetic wave, wavelength, frequency, wave speed and uses those terms in the approved AQA GCSE Physics Waves context.