wave

Dictionary


  • one of a series of ridges that moves across the surface of a liquid (especially across a large body of water) a movement like that of a sudden occurrence or increase in a specified phenomenon
  • "a wave of settlers"
  • "troops advancing in waves" (physics) a movement up and down or back and forth something that rises rapidly
  • "a wave of emotion swept over him"
  • "there was a sudden wave of buying before the market closed"
  • "a wave of conservatism in the country led by the hard right" the act of signaling by a movement of the hand a hairdo that creates undulations in the hair an undulating curve a persistent and widespread unusual weather condition (especially of unusual temperatures)
  • "a heat wave" a member of the women's reserve of the United States Navy
  • originally organized during World War II but now no longer a separate branch signal with the hands or nod
  • "She waved to her friends"
  • "He waved his hand hospitably" move or swing back and forth
  • "She waved her gun" move in a wavy pattern or with a rising and falling motion
  • "The curtains undulated"
  • "the waves rolled towards the beach" twist or roll into coils or ringlets
  • "curl my hair, please" set waves in
  • "she asked the hairdresser to wave her hair"

  • Wikipedia


    This article is about waves in the most general scientific sense; a separate article focuses on ocean surface waveocean waves. For other meanings see wave (disambiguation).''A wave is a disturbance that propagates in a periodically repeating fashion, often transferring energy. A mechanical wave exists in a medium (bearer)medium (which on deformation is capable of producing elastic restoring forces) through which they travel and can transfer energy from one place to another without any of the particles of the medium being displaced permanently; there is no associated mass transport. Instead, any particular point oscillationoscillates around a fixed position. However, electromagnetic radiation, and probably gravitational radiation are not mechanical waves, and can travel through a vacuum, without a medium.Waves are characterised by ''crests'' (highs) and ''troughs'' (lows), either perpendicular (in the case of transverse waves) or parallel (in the case of longitudinal waves) to wave motion.

    The medium which carries a wave - A medium that can carry a wave is classified by one or more of the following properties:
  • A ''linear medium'' if the amplitudes of different waves at any particular point in the medium can be added.
  • A ''bounded medium'' if it is finite in extent, otherwise ''unbounded''.
  • A ''uniform medium'' if its physical properties are unchanged at different locations in space.
  • An ''isotropic medium'' if its physical properties are the ''same'' in different directions.

    Examples of waves -
  • Ocean surface waves, which are perturbations that propagate through water (see also surfing and tsunami).
  • Visible light, radio waves, x-rays, gamma rays, infraredinfrared rays, and ultravioletultraviolet rays make up electromagnetic radiation. In this case propagation is possible without a medium, through vacuum. These electromagnetic waves travel at about speed of light300,000 km/s.
  • Sound - a mechanical wave that propagates through air, liquid or solids, and is of a frequency detected by the earauditory system. Similar are seismic waves in earthquakes, of which there are the S, P and L kinds.
  • Gravitational waves, which are fluctuations in the gravitational field predicted by General relativity. These waves are nonlinear.

    Characteristic properties - All waves have common behaviour under a number of standard situations. All waves can experience the following:
  • Reflection – the change of direction of waves, due to hitting a reflective surface.
  • Refraction – the change of direction of a wave due to them entering a new medium.
  • Diffraction – the spreading out of waves, for example when they travel through a small slit.
  • Interference – the Superposition principlesuperposition of two waves that come into contact with each other.
  • Dispersion (optics)Dispersion – the splitting up of waves by frequency.
  • Rectilinear propagation – the movement of waves in straight lines.

    Transverse and longitudinal waves - Transverse waves are those with vibrations perpendicular to the wave's direction of travel; examples include waves on a string and electromagnetic waves. Longitudinal waves are those with vibrations along the wave's direction of travel; examples include most sound waves. ripple tankRipples on the surface of a pond are actually a combination of transverse and longitudinal waves; therefore, the points on the surface follow elliptical paths.

    Polarization - Transverse waves can be polarizationpolarized. Unpolarised waves can oscillate in any direction in the plane perpendicular to the direction of travel, while polarized waves oscillate in only one direction perpendicular to the line of travel.

    Physical description of a wave - Waves can be described using a number of standard variables including: frequency, wavelength, amplitude and period (physics)period.The amplitude of a wave is the measure of the magnitude of the maximum disturbance in the medium during one wave cycle, and is measured in units depending on the type of wave. For examples, waves on a string have an amplitude expressed as a distance (meters), sound waves as pressure (pascals) and electromagnetic waves as the amplitude of the electric field (volts/meter). The amplitude may be constant (in which case the wave is a ''c.w.'' or ''continuous wave'') or may vary with time and/or position. The form of the variation of amplitude is called the ''envelope'' of the wave.The period (''T'') is the time for one complete cycle for an oscillation of a wave. The frequency (''F'') is how many periods per unit time (for example one second) and is measured in hertz. These are related by::f=\frac When waves are expressed mathematically, the ''angular frequency'' (''ω'', radians/second) is often used; it is related to the frequency ''f'' by::f=\frac .

    Travelling waves - Waves that remain in one place are called ''standing waves'' - e.g. vibrations on a violin string.Waves that are moving are called ''travelling waves'', and have a disturbance that varies both with time ''t'' and distance ''z''. This can be expressed mathematically as::y=A(z,t) \cos (\omega t - kz + \phi),\,fwhere ''A''(''z'', ''t'') is the amplitude envelope of the wave, ''k'' is the ''wave number'' and φ is the ''phase (waves)phase''. The velocity ''v'' of this wave is given by::v=\frac = \lambda f,where ''λ'' is the ''wavelength'' of the wave.

    Propagation through strings - The speed of a wave travelling along a string (v) is directly proportional to the square root of the tension (T) over the linear density (ρ)::v=\sqrt }.This equation can be found using dimensional analysis

    The wave equation - The wave equation is a differential equation which describes a harmonic wave passing through a medium, discussed above. The equation has different forms depending on how the wave is transmitted, and on what medium. Not all waves are sinusoidal. One example of a non-sinusoidal wave is a pulse that travels down a rope resting on the ground, extending in direction ''x'', travelling at velocity ''c''. The height of the pulse above the ground is φ. The distance the pulse travels between some time ''t'' and time 0 is ''ct''.In one dimension the wave equation has the form:\frac \frac =\frac .A general solution, given by d'Alembert !is:\phi(x,t)=F(x-c t)+E(x+ct).? F and E can be considered to be the shapes of two pulses travelling down the rope, one in the ''+x'' direction, and one in the ''-x'' direction. If we substitute for ''x'' above, instead directions ''x'', ''y'', ''z'', we then can describe a wave propagating in three dimensions. A non-linear wave-equation can cause mass transport.The Schrödinger equation describes the wave-like behaviour of particles in quantum mechanics. Solutions of this equation are wave functions which can be used to describe the probability density of a particle. Quantum mechanics also describes particle properties that other waves, such as light and sound, have on the atomic scale and below.

    External links -
  • lightandmatter.com - Vibrations and Waves - an online textbook
  • kestrel.nmt.edu - A Radically Modern Approach to Introductory Physics - an online physics textbook that starts with waves rather than mechanics

    See also - wiktionary
  • List of wave topics
  • Capillary waves
  • Doppler effect
  • Group velocity
  • Phase velocity
  • Ripple tank
  • Standing wave
  • Audience wave
  • Ocean surface wave
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  • Websites


    Sinnflut - die offizielle Band-Homepage
    Eine Band, die zwischen Klassik und Moderne das Ziel der menschlichen Berührung, auf tiefste und dunkelste Art und Weise, anstrebt ...
    http://www.traenendes-herz.com/

    Sea-Image Corporation
    Our mission is to bring technologies to the marine marketplace that: 1. Increase safety at sea 2. Enable more efficient maritime operations 3. Enhance our knowledge of the oceans
    http://www.sea-image.com/

    Audiobulb Records
    Audiobulb Records is a UK label holding a global artist roster brought together under the banner of exploratory electronic music. The term exploratory invites artists to create without the restriction of having to stay within a specified territory. Our focus is quality, detail, intricacy and emotionality within electronic music. The sounds from our artists embrace glitch and groove, IDM, environmental ambience, microsounds and idiosyncratic dance beats.
    http://www.audiobulb.com/

    Erik Wøllo, official website
    Erik Wøllo is a norwegian composer and musician. Electronic and acoustic soundscapes. Guitarist. Recording artist. VST instrument creator.
    http://www.wollo.com/

    New Wave Truss - Total Structures Inc.
    Website of Total Structures Carbon Fiber New Wave truss.
    http://www.newwavetruss.com/

    XtraX Undergroundfashion
    The shop for Gothic, Fetish, Wave, HorroPunk, Psycho- & Rockabilly, Dark-Metal and CyberRock-Fashion.
    http://www.x-tra-x.org/

    *FlutterbyButterfly*
    Creative Handcrafted Clothing & Accessories featuring eco-friendly process and unique designs.
    http://www.flutterbybutterfly.net/

    MetalWave
    Italian Metal Underground Webzine
    http://www.metalwave.it/

    Solo Explorer - wav to MIDI conversion software
    Solo Explorer is a wave to MIDI conversion, automatic music transcription (recognition), and score editing software for Windows. It extracts music score out of the the monophonic audio records. You can display, play, edit, and save your music. Solo Explorer supports both prerecorded Windows PCM and direct audio input. It has simple and easy-to-use interface.
    http://www.recognisoft.com/

    Radio 19/4 - Jazz, Pop, Noize
    Radio 19/4 for more than eleven Years on Antenne Muenster's Open Channel, Ukw 95,4 mhz. 4. Monday/Month + Specials. Length: one hour. Profile: Jazz, Pop, Noise - no Mainstream - Music somewhat alternartive. Range: 80km around Muenster City + Promotion via Website-reviews.
    http://www.radio19-4.de/

    azrael69
    music for electro people
    http://www.azrael69.de/

    Official Website For Recording Artist Ari Gold
    Check here for latest info on Global Popster Ari Gold. Tour dates added weekly.
    http://www.arigold.com/

    angelspur persians
    breeding and showing solid colour persians with a focus on whites in all eye colours
    http://www.angelspur.com/

    Acts 4:13 Website
    Christian evangelistic discipleship ministry focusing on Reformed Calvinistic theology and salvation by the sovereign grace of God alone.
    http://www.acts413.org/

    BLACK CHANNEL Air + Net Radio Show
    BLACK CHANNEL Air + Net Radio Show presents the world of WAVE, GOTHIC, INDUSTRIAL, DARK TECHNO, Electro, RITUAL, EXPERIMENTAL, Ambient and Avangarde via Streaming Real Audio Broadcasting
    http://www.blackchannel.org/

    Coolboards.it - Skateboard Snowboard Surf
    news curiosità mercatino dell'usato previsioni meteo neve e onde tutti i tricks tanti filmati e foto da scaricare dal mondo dello skateboard, dello snowboard e del surf da onda
    http://www.coolboards.it/

    Rogue Wave Software
    Provider of a wide-range of components for the cross-platform C++ market including mathematical, financial and statistical class libraries.
    http://www.roguewave.com

    Wave Sport Kayaks
    Manufactures whitewater kayaks and paddling accessories. Find dealers worldwide. Lifestyle section updated monthly. Includes information on pro-team rodeo results. Located in Trinity, NC.
    http://www.wavesport.com/

    WAVE3 Louisville
    Program listings, news, weather, sports, and community events.
    http://www.WAVE3.com

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