A resonator capable of vibrating is a system whose components are tuned to a specific frequency ( resonant frequency ) such that the resonator swings upon excitation at this frequency (see resonance).
→ see also: Sound box
Acoustic resonators ( airborne noise ) consist of a closed or partially open air volume. The elasticity of the air in a cavity and the mass of air in, for example, tube-like opening therein leads to certain resonance frequencies. The Helmholtz resonator is a partly open cavity, as is a simple tube (see also Rijke tube).
Mechanical resonators consist of discrete springs and masses ( tuning fork ) or oscillating bodies ( piezoceramic resonators).
Hydro-mechanical resonators represent, among others, Beck resonators in which a ( partial) definable ( incompressible ) fluid mass moves through reflection on their boundaries in the form of a standing wave. See Tideresonanz, wave resonance.
Electrical resonators ( tank circuits ) are made of capacitors ( capacitors) and coils ( inductors ). In this and the magnetic field in the coil is involved.
Electromagnetic resonators are resonant cavities for electromagnetic waves. They are, for example, in laser ( laser resonator optical resonator ), in the klystron, in Dielectric resonator in particle accelerators ( see, eg, linear accelerator ) or in the cavity ring-down spectroscopy ( CRDS ) was used.