Intensification and prolongation of sound, especially of a musical tone, produced by sympathetic vibration. Intensification of vocal tones during articulation, as by the air cavities of the mouth and nasal passages. The sound produced by diagnostic percussion of the normal chest. The property of a compound having simultaneously the characteristics of two or more structural forms that differ only in the distribution of electrons. Such compounds are highly stable and cannot be properly represented by a single structural formula.
Many inorganic radicals exhibit resonance, as do aromatic compounds.
The condition resembles similar combined effects in other systems, discussed below. If an alternating voltage of the resonant frequency is applied to a circuit in which capacity and inductance are connected in series, the circuit conducts a maximum amount of current. When the capacitance and inductance are connected in parallel, little current will pass. Resonant circuits are used in electric equipment to select or reject currents of specific frequencies. Resonance can also occur in mechanical, structural, and acoustical systems when a system is excited by the continued application of forces at the natural frequency.