Mini:Resonance
In physics, resonance is the phenomenon of producing large amplitude of vibrations by a small periodic driving force. It is the tendency of a system to oscillate at maximum amplitude at a certain frequency. This frequency is known as the system's resonance frequency (or resonant frequency). When damping is small, the resonance frequency is approximately equal to the natural frequency of the system, which is the frequency of free vibrations. Under resonance condition the energy supplied by the driving force is sufficient to overcome friction.