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Jump to navigationJump to searchNew page: Image:lighterstill.jpg In physics, '''resonance''' is the tendency of a system to oscillate at its maximum amplitude, associated with specific frequencies known as ...
[[Image:lighterstill.jpg]]
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.
== 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.
Resonance occurs widely in [[nature]], and is exploited in many man-made devices. It is the mechanism by which virtually all sinusoidal [[wave]]s and vibrations are generated. Many [[sound]]s we hear, such as when hard objects of metal, glass, or wood are struck, are caused by brief resonant vibrations in the object. Light and other short wavelength electromagnetic radiation is produced by resonance on an atomic scale, such as electrons in atoms. Other examples are:
* acoustic resonance of [[musical instruments]]
* the timekeeping mechanisms of all modern clocks and watches: the balance wheel in a mechanical watch and the quartz crystal in a quartz watch
* [[tidal resonance]]
* [[orbital resonance]] as exemplified by some [[moons]] of the solar system's [[gas giants]]
* the resonance of the basilar membrane in the cochlea of the ear, which enables people to distinguish different frequencies or tones in the sounds they hear.
* 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.
* 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]
[[Category: Physics]]
[[Category: Music]]
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.
== 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.
Resonance occurs widely in [[nature]], and is exploited in many man-made devices. It is the mechanism by which virtually all sinusoidal [[wave]]s and vibrations are generated. Many [[sound]]s we hear, such as when hard objects of metal, glass, or wood are struck, are caused by brief resonant vibrations in the object. Light and other short wavelength electromagnetic radiation is produced by resonance on an atomic scale, such as electrons in atoms. Other examples are:
* acoustic resonance of [[musical instruments]]
* the timekeeping mechanisms of all modern clocks and watches: the balance wheel in a mechanical watch and the quartz crystal in a quartz watch
* [[tidal resonance]]
* [[orbital resonance]] as exemplified by some [[moons]] of the solar system's [[gas giants]]
* the resonance of the basilar membrane in the cochlea of the ear, which enables people to distinguish different frequencies or tones in the sounds they hear.
* 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.
* 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]
[[Category: Physics]]
[[Category: Music]]
