Wavelength

The distance measured perpendicular to the wavefront in the direction of propagation between two successive points in the wave separated by one period. Equals the ratio of the speed of sound in the medium of the fundamental frequency.

In sound (Audio frequency range), the wavelength depends on the speed of sound in the medium in question. Propagation in air is very slow, approximately 340 meters per second. Wavelength equals the speed of sound divided by frequency. Hence, the wavelength of a 1 kHz sinewave is 340/1000 = 0.34 m.

In radio transmission (Radio frequency range), the electromagnetic waves propagate at approximately 300,000 km/s. Hence, the wavelength of a radio wave of 500 MHz equals 300.000.000/500,000,000 m = 0,6 m.