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In [[physics]], '''resonance'''  is the tendency of a system to oscillate at its maximum amplitude, associated with specific [[Frequency|frequencies]] known as the system's ''resonance frequencies'' (or ''resonant frequencies'').  At these frequencies, even small periodic driving forces can produce large amplitude vibrations, because the system stores vibrational [[energy]].  When damping is small, the resonance frequency is approximately equal to the natural frequency of the system, which is the frequency of free vibrations.  Resonant [[phenomena]] occur with all types of vibrations or waves: there is mechanical resonance, acoustic resonance, electromagnetic resonance, nuclear magnetic resonance (NMR), Electron paramagnetic resonance (ESR) and resonance of [[quantum]] wave functions. Resonant systems can be used to generate vibrations of a specific frequency, or pick out specific frequencies from a complex vibration containing many frequencies.

In [[physics]], '''resonance'''  is the tendency of a system to oscillate at its maximum amplitude, associated with specific [[Frequency|frequencies]] known as the system's ''resonance frequencies'' (or ''resonant frequencies'').  At these frequencies, even small periodic driving forces can produce large amplitude vibrations, because the system stores vibrational [[energy]].  When damping is small, the resonance frequency is approximately equal to the natural frequency of the system, which is the frequency of free vibrations.  Resonant [[phenomena]] occur with all types of vibrations or waves: there is mechanical resonance, acoustic resonance, electromagnetic resonance, nuclear magnetic resonance (NMR), Electron paramagnetic resonance (ESR) and resonance of [[quantum]] wave functions. Resonant systems can be used to generate vibrations of a specific frequency, or pick out specific frequencies from a complex vibration containing many frequencies.

Resonance was discovered by [[Galileo Galilei]] with his investigations of [[pendulum]]s beginning in 1602.

Resonance was discovered by [[Galileo Galilei]] with his investigations of [[pendulum]]s beginning in 1602.

== Examples ==

== Examples ==

One familiar example is a playground swing, which acts as a [[pendulum]]. Pushing a [[person]] in a swing in time with the natural interval of the swing (its resonance frequency) will make the swing go higher and higher (maximum amplitude), while attempts to push the swing at a faster or slower tempo will result in smaller arcs. This is because the energy the swing absorbs is maximized when the pushes are 'in [[phase]]' with the swing's oscillations, while some of the swing's energy is actually extracted by the opposing force of the pushes when they are not.

One familiar example is a playground swing, which acts as a [[pendulum]]. Pushing a [[person]] in a swing in time with the natural interval of the swing (its resonance frequency) will make the swing go higher and higher (maximum amplitude), while attempts to push the swing at a faster or slower tempo will result in smaller arcs. This is because the energy the swing absorbs is maximized when the pushes are 'in [[phase]]' with the swing's oscillations, while some of the swing's energy is actually extracted by the opposing force of the pushes when they are not.

* creation of [[coherent]] light by optical resonance in a [[laser]]

* creation of [[coherent]] light by optical resonance in a [[laser]]

* material resonances in atomic scale are the basis of several [[spectroscopy|spectroscopic]] techniques that are used in [[condensed matter physics]].  Examples include [[Nuclear Magnetic Resonance]], [[Mössbauer effect]], [[Electron Spin Resonance]], and many others.

* material resonances in atomic scale are the basis of several [[spectroscopy|spectroscopic]] techniques that are used in [[condensed matter physics]].  Examples include [[Nuclear Magnetic Resonance]], [[Mössbauer effect]], [[Electron Spin Resonance]], and many others.

* the shattering of a [[crystal]] wineglass when exposed to a musical [[tone]] of the right pitch (its resonance frequency).[http://en.wikipedia.org/wiki/Resonance]

* the shattering of a [[crystal]] wineglass when exposed to a musical [[tone]] of the right pitch (its resonance frequency).[https://en.wikipedia.org/wiki/Resonance]

[[Category: Physics]]

[[Category: Physics]]

[[Category: Music]]

[[Category: Music]]