frequency

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frequency:

see harmonic motionharmonic motion,
regular vibration in which the acceleration of the vibrating object is directly proportional to the displacement of the object from its equilibrium position but oppositely directed.
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; wavewave,
in physics, the transfer of energy by the regular vibration, or oscillatory motion, either of some material medium or by the variation in magnitude of the field vectors of an electromagnetic field (see electromagnetic radiation).
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.

Frequency (wave motion)

The number of times which sound pressure, electrical intensity, or other quantities specifying a wave vary from their equilibrium value through a complete cycle in unit time. The most common unit of frequency is the hertz (Hz), which is equal to 1 cycle per second. In one cycle there is a positive variation from equilibrium, a return to equilibrium, then a negative variation, and return to equilibrium. This relationship is often described in terms of the sine wave, and the frequency referred to is that of an equivalent sine-wave variation in the parameter under discussion. See Frequency measurement, Sine wave, Wave motion

frequency

Symbol: f , ν. The number of oscillations per unit time of a vibrating system. Frequency is measured in hertz. The frequency of a wave is the number of wave crests passing a point per unit time. For light and other electromagnetic radiation, it is related to wavelength λ by ν = c /λ, where c is the speed of light.

Frequency

 

The frequency of an event A is the ratio m/n of the number m of occurrences of A in a given series of trials to the total number n of trials. If the trials are independent and there is a definite probability p of the occurrence of A in an individual trial, then, for arbitrarily small ∊ > 0, at sufficiently large m it is practically certain that the frequency m/n satisfies the inequality

(seeLARGE NUMBERS, LAW OF and PROBABILITY).

The term “frequency” is used in mathematical statistics to designate the number of elements of a set that have a specified attribute.

frequency

[′frē·kwən·sē]
(physics)
The number of cycles completed by a periodic quantity in a unit time.
(statistics)
The number of times an event or item falls into or is expected to fall into a certain class or category.

frequency

The number of oscillations per second (a) of the current or voltage in an alternating-current electric circuit, or (b) of a sound wave, or (c) of a vibrating solid object; expressed in hertz (abbr. Hz) or in cycles per second (abbr. cps).

frequency

frequencyclick for a larger image
i. The number of recurrences of a periodic phenomenon in a unit of time.
ii. The number of cycles completed in one second. One cycle per second is the basic unit of measurement of frequency and is called a hertz.
iii. The number of services operated by an airline per day or per week over a particular route.

frequency

1. Physics the number of times that a periodic function or vibration repeats itself in a specified time, often 1 second. It is usually measured in hertz.
2. Ecology
a. the number of individuals of a species within a given area
b. the percentage of quadrats that contains individuals of a species

frequency

The number of oscillations (vibrations) in one second. Frequency is measured in Hertz (Hz), which is the same as "oscillations per second" or "cycles per second." For example, the alternating current in a wall outlet in the U.S. and Canada is 60Hz. Electromagnetic radiation is measured in kiloHertz (kHz), megahertz (MHz) and gigahertz (GHz). See wavelength, frequency response, audio, carrier and space/time.


Frequency
The frequency is the number of oscillations per second. The higher the frequency (the closer the ripples would be in this diagram) and the shorter the wavelength.
References in periodicals archive ?
Le traitement de fond permet de diminuer la frequence de la crise.
Au-dela de la frequence d'envoi, il faut s'assurer de la valeur ajoutee des communications pour que le contenu redactionnel soit bien percu par le client.
Les protocoles de rTMS proposes utilisent soit une stimulation << facilitatrice >> a haute frequence sur le CPFDL gauche, soit une stimulation <<inhibitrice>> a basse frequence sur le CPFDL droit (Lefaucheur et al.
Results: In the experimental group, the mean resonance frequence analysis value was 60.
Natural Radio, et realises en Finlande, en Ecosse et au Quebec, en exploitant les basses frequences emanant de phenomenes naturels comme les aurores boreales.
Pensons par exemple a tous les candidats aux elections federales et a la frequence des mots figurant dans les transcriptions des debats parlementaires.
L'evolution reste marquee par la frequence de metastases ganglionnaires perirenales au moment du diagnostic (29 %)[sup.
Le stimulateur va creer une impulsion electrique qui permettra au coeur de battre a une frequence reguliere.
the most important species in the standing vegetation had a frequence of only 13% in the seed bank.
De plus, la qualite du fonctionnement de l'ecole varie selon la nature et la frequence des interventions des directions, ce qui tend a demontrer l'importance de leur travail de gestionnaire.
Les releves acridiens sont effectues entre le Sahara algerien central et meridional, zones considerees comme a haute frequence de reproduction, en fonction du regime pluviometrique mediterraneen ou tropical (Sitouh 1976, Chara 1998, GuendouzBenrima 2005, Guendouz-Benrima 2007).
Mora, dans une etude sur la prosodie de l'espagnol du Venezuela (Mora, 1996) montre que les deux parametres concernes pour l'accent sont la duree et la frequence fondamentale.