When two identical simple harmonic oscillators are coupled by a linear spring that has a spring constant the system has two resonant frequencies. There is a resonance at their natural frequency, when the oscillators oscillate in phase and a resonance at the frequency when the oscillators are 180° out of phase. These oscillations are referred to individually as the symmetric and antisymmetric modes or collectively as the normal modes. The frequencies are called the normal frequencies.
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© 2006 American Association of Physics Teachers.
2006
American Association of Physics Teachers
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