Frequenza

Frequenza, in Italian, is the concept known in English as frequency. It denotes the rate at which a repeating event occurs per unit of time. The standard SI unit is the hertz (Hz), defined as one cycle per second. The frequency f is the reciprocal of the period T: f = 1/T.

In physics and engineering, frequenza describes oscillations and waves. A signal or motion with frequency f repeats f times per second; angular frequency ω = 2πf provides a measure in radians per second. For waves, the product fλ equals the wave speed in the medium, where λ is the wavelength.

In music, frequenza determines pitch. Each note corresponds to a frequency; higher notes have higher frequencies. A commonly used reference is A4 = 440 Hz, with octaves spaced by factors of two in frequency.

In signal processing and communications, frequenza is central to sampling and bandwidth. The sampling frequency fs must be at least twice the maximum frequency in the signal (Nyquist criterion) to avoid aliasing. Radio and optical systems use defined frequency bands to separate channels and services.

In statistics, frequenza refers to how often a value occurs in a data set. Absolute frequency counts occurrences; relative frequency expresses the proportion of observations. Frequency distributions and cumulative frequency help summarize and analyze data.