Editing Q factor (section)

=== Bandwidth definition ===
In the context of resonators, there are two common definitions for {{mvar|Q}}, which are not exactly equivalent. They become approximately equivalent as {{mvar|Q}} becomes larger, meaning the resonator becomes less damped. One of these definitions is the frequency-to-bandwidth ratio of the resonator:<ref name="Green"/>

<math display="block">Q \mathrel\stackrel{\text{def}}{=} \frac{f_\mathrm{r}}{\Delta f} = \frac{\omega_\mathrm{r}}{\Delta \omega},</math>

where {{math|''f''<sub>r</sub>}} is the resonant frequency, {{math|Δ''f''}} is the '''resonance width''' or [[full width at half maximum]] (FWHM) i.e. the bandwidth over which the power of vibration is greater than half the power at the resonant frequency, {{math|1= ''ω''<sub>r</sub> = 2''πf''<sub>r</sub>}} is the [[angular frequency|angular]] resonant frequency, and {{math|Δ''ω''}} is the angular half-power bandwidth.

Under this definition, {{mvar|Q}} is the reciprocal of [[fractional bandwidth]].