| Dictionary, Encyclopedia and Thesaurus - The Free Dictionary 1,763,183,349 visitors served. |
|
Dictionary/ thesaurus | Medical dictionary | Legal dictionary | Financial dictionary | Acronyms | Idioms | Encyclopedia | Wikipedia encyclopedia | ? |
frequency |
Also found in: Dictionary/thesaurus, Medical, Legal, Wikipedia, Hutchinson | 0.02 sec. |
|
frequency: see harmonic motion harmonic 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. ..... Click the link for more information. ; wave wave, 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 ). ..... Click the link for more information. . frequencyNumber of waves that pass a fixed point per unit time; also, the number of cycles or vibrations undergone in unit time by a body in periodic motion. Frequency f is the reciprocal of the time T taken to complete one cycle (the period), or 1/T. The frequency with which earth rotates is once per 24 hours. Frequency is usually expressed in units called hertz (Hz). One hertz is equal to one cycle per second; one kilohertz (kHz) is 1,000 Hz, and one megahertz (MHz) is 1,000,000 Hz. The musical pitch A above middle C (the A string of a violin) has been widely standardized as 440 Hz. frequencyThe 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 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 [′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 (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 How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
|
| ? Mentioned in | ? References in periodicals archive | ||
|---|---|---|---|
| Both groups showed improvements in nocturnal urinary frequency, but only the group using PFME alone improved in terms of daytime urinary frequency. Holland pointed out that medications to control urinary frequency can be added to a plan that includes ISC. Conversely, urinary frequency and glomerular filtration increase during pregnancy (Becker et al. |
| Encyclopedia |
| Free Tools: |
For surfers:
Free toolbar & extensions |
Word of the Day |
Help
For webmasters: Free content | Linking | Lookup box | Double-click lookup | Partner with us |
|---|