frequency


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Related to frequency: frequency modulation, Sound frequency

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 classic literature ?
This particular example is brought into view, not as a proof of any peculiar merit, for the priority in those instances was probably accidental; and still less of any advantage in SEPTENNIAL elections, for when compared with a greater frequency they are inadmissible; but merely as a proof, and I conceive it to be a very substantial proof, that the liberties of the people can be in no danger from BIENNIAL elections.
As the light in the amphitheater increased the females augmented the frequency and force of their blows until presently a wild, rhythmic din pervaded the great jungle for miles in every direction.
The din of the drum was now increased, as well as the frequency of the blows, and the warriors, as each approached the victim of the hunt and delivered his bludgeon blow, joined in the mad whirl of the Death Dance.
Certainly less frequency would suffice for all important and hearty communications.
It is the frequency of the latter kind of change, and the comparatively simple nature of the laws governing the simultaneous alterations of appearances in such cases, that have made it possible to treat a physical object as one thing, and to overlook the fact that it is a system of particulars.
The primary physical effects of damping are that it limits the steady state motion of structures at their natural frequency and increases the rate of decay of vibration.
Most NVH issues are analyzed in the frequency domain, which means that noise and vibration problems are analyzed in terms of sine waves of specific frequency (hz or cycles per second).
Instead, physicists laboriously created so-called frequency chains starting with the cesium signal.
Electromagnetic waves vary in frequency, or the amount of energy they contain.
Yet servo motors are much more efficient than a-c frequency motors.
an international energy industry consulting firm, was commissioned by Beacon Power as a subcontractor under a previously announced contract to design a 20-megawatt Smart Energy Matrix frequency regulation power plant.
This system measures specimen stiffness accurately to within 1% for frequencies up to about 10% of resonance frequency (erf.