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3: Resonance

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    Resonance is a key concept in the production of sound in instruments and in acoustics. We will come across it many more times in this book. The natural frequency (\(f_{o}\) measured in hertz) is the frequency at which an oscillating system naturally wants to vibrate. For a mass on a spring, this is determined by the size of the mass and the stiffness of the spring; a stiffer spring has a higher natural frequency as we saw in the previous chapter. To keep a system vibrating in the presence of friction we have to keep pushing it with a periodic force. The frequency of this periodic driving force is called the driving frequency, \(f\) which is totally independent of the natural frequency (we can push our mass on a spring at a frequency different from the frequency at which it wants to vibrate).

    Key Terms:

    Natural frequency, driving frequency, angular frequency, damped harmonic motion, driven harmonic motion, resonance, resonator, Helmholtz resonance, Quality or Q-factor.

    3: Resonance is shared under a CC BY-NC-SA 3.0 license and was authored, remixed, and/or curated by Kyle Forinash and Wolfgang Christian via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.