Taajuuden

Taajuuden is the Finnish term for frequency, the rate at which a periodic phenomenon repeats per unit time. In physics and engineering, taajuus is commonly denoted f and measured in hertz (Hz). One hertz equals one cycle per second. The reciprocal of taajuus gives the period, T = 1/f, and the angular frequency ω = 2πf expresses the same rate in radians per second.

Taajuuden has wide-ranging applications: in acoustics, it determines pitch; in telecommunications, it defines channels and modulation schemes; in optics, the optical taajuus is associated with photon energy. Signals contain a range of taajuudet (the frequency spectrum). The bandwidth describes how broad that range is. The sampling theorem relates taajuuden content to the required sampling rate, with the Nyquist frequency being half the sampling rate.

Resonance occurs when a driving taajuus matches a system’s natural frequency, producing amplified oscillations. Frequency-domain analysis, such as Fourier transform, represents a signal as a sum of sinusoids at individual taajuudet, enabling analysis and filtering in the frequency domain. In practice, selecting specific taajuudet allows tuning radios, shaping audio signals, and controlling laser operations by targeting optical taajuus. Overall, taajuuden is a central concept across science and engineering, linking time-based phenomena to their spectral content.