Driven Oscillation
Definition
A vibration kept going by repeated pushes — pushing a swing at just the right moment each cycle is a driven oscillation.
Technical definition
With a periodic driving force F₀cos(ωt), the steady-state amplitude peaks when the driving frequency matches the natural frequency (resonance).
Example
A microwave oven drives water molecules near 2.45 GHz — close to a rotational resonance — which is why the food heats while the plate stays cool.
Common confusion
A driven oscillator does not automatically end up at resonance. The driver sets the frequency — the system is forced to vibrate at the driving frequency, with amplitude largest near resonance.