Pendulums, time pieces. Average Annual temperature
Hertz (Hz) is a unit of frequency of “one cycle per second”.
Sound Waves
Music notes/tones/frequencies and the Doppler affect We perceive sound as an oscillation of pressure; the pitch of the sound is the frequency of that oscillation as a sinusoidal wave. Adult human ear between 20 Hz and 20 kHz; corresponding to wavelengths of 56ft to ⅔in (in atmospheric pressure) pure tone have a single sine wave
Electromagnetic Waves
Radio frequencies, AM/FM/HAM
Fourier analysis