Resonance

The resonance effect refers to the vibration, in air or through solids, of a solid element. The production of resonance requires a relatively high acoustic level and a concordance between the exciting frequency and the object put into vibration. Modal resonance refers to the phenomenon of standing waves in a three-dimensional space. Note in everyday language the term "resonance" includes any acoustically observable sonic effect, particularly reverberation. Resonance is a general physical phenomenon found in all periodic sinusoidal movements, particularly in mechanics, acoustics, optics, and electricity. The identity of the role of certain elements make it possible to perform studies by analogy, referring to a general system that includes the actual case of resonance at the sonic level. For the phenomenon of resonance to manifest itself, the periodic sinusoidal movement must fulfil the four following conditions: The system must have a characteristic frequency. It must be maintained with a constant energy input (because of the loss of energy due to friction, which must always be taken into consideration). The loss of exterior energy must be low enough that the transmitted energy remains superior or equal to the internal loss of the system. The exciting frequency must be equal or almost equal to the characteristic frequency of the system. Under these conditions, theoretically resonance produces an infinite gain in amplitude. At least in the normal mode, corresponding to the lowest frequency, called the fundamental.