Resonance

The amplitude of the driven oscillation is maximum when the denominator in this expression is minimal:

\[A(\omega) = \frac{F_0 / m}{\sqrt{\left(\omega^2 - \omega_0^2\right)^2 + \left(\frac{\gamma \omega}{m}\right)^2}}.\]

This occurs when the angular frequency of the driving force is close to the natural angular frequency of the system:

\[\omega \approx \omega_0.\]