resonanssi
Resonanssi, Finnish for resonance, is the phenomenon where a system responds with larger oscillation amplitudes at certain driving frequencies. A system has a natural or resonant frequency at which energy transfer between the driving force and the system is most efficient. When the driving frequency approaches this frequency, even small periodic forces can produce large responses if damping is small.
Common contexts include mechanical systems (pendulums, bridges, guitar strings) and acoustics (sound in air, air columns).
In electronics, resonance occurs in LC circuits where inductive and capacitive reactances cancel at the resonant
Resonance also appears in optics, molecular and atomic transitions (optical resonance), and in magnetic resonance techniques
Resonance is exploited for tuning radios and filters, musical instruments, and experimental measurements, but must be