Sähköresonanssi

Sähköresonanssi, often translated as electrical resonance, is a phenomenon that occurs in an electrical circuit containing both inductance and capacitance. When the frequency of an applied alternating voltage matches a specific natural frequency of the circuit, the circuit exhibits resonance. At this resonant frequency, the inductive and capacitive reactances cancel each other out, leading to a significant increase in the current amplitude in a series resonant circuit or the voltage amplitude across the components in a parallel resonant circuit.

This effect is analogous to mechanical resonance, where an object vibrates with maximum amplitude when driven at its natural frequency. In electrical circuits, the resonant frequency (f₀) is determined by the values of the inductance (L) and capacitance (C) according to the formula f₀ = 1 / (2π√(LC)). Above or below this frequency, the impedance of the circuit increases, and the current or voltage amplitudes decrease.

Electrical resonance has numerous applications. It is fundamental to the tuning circuits in radios and televisions, allowing them to select specific broadcast frequencies. It is also utilized in filters, oscillators, and various signal processing systems. The quality factor (Q) of a resonant circuit describes how sharp or broad the resonance is; a higher Q factor indicates a narrower bandwidth and a more pronounced peak in amplitude. Understanding and controlling sähköresonanssi is crucial in the design and operation of many electronic devices.