Resonant frequency

Resonant frequency is the natural frequency at which an object or system vibrates most easily. When an external force matches this frequency, the object responds with larger vibrations. Think of it like pushing a swing: if you push at the right moment (the swing's resonant frequency), it goes higher. This phenomenon is seen in musical instruments, bridges, and even atoms. If the frequency of external forces is too far from the resonant frequency, the object won't vibrate much; it's only when they align that significant movement occurs, which can lead to interesting effects, including structural failures.