Wavelength

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In physics, the wavelength of a sinusoidal wave is the spatial period of the wave – the distance over which the wave's shape repeats. It is usually determined by considering the distance between consecutive corresponding points of the same phase, such as crests, troughs, or zero crossings, and is a characteristic of both traveling waves and standing waves. Wavelength is commonly designated by the Greek letter lambda (λ). The concept can also be applied to periodic waves of non-sinusoidal shape. The term wavelength is also sometimes applied to modulated waves, and to the sinusoidal envelopes of modulated waves or waves formed by interference of several sinusoids.

Assuming a sinusoidal wave moving at a fixed wave speed, wavelength is inversely proportional to frequency: waves with higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths.

Examples of wave-like phenomena are sound waves, light, and water waves. A sound wave is a periodic variation in air pressure, while in light and other electromagnetic radiation the strength of the electric and the magnetic field vary. Water waves are periodic variations in the height of a body of water. In a crystal lattice vibration, atomic positions vary periodically in both lattice position and time.

Wavelength is a measure of the distance between repetitions of a shape feature such as peaks, valleys, or zero-crossings, not a measure of how far any given particle moves. For example, in waves over deep water a particle in the water moves in a circle of the same diameter as the wave height, unrelated to wavelength.

For more information about Wavelength, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with wavelength

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Building a more versatile laser

Building a more versatile laser

Physics / Optics & Photonics

created Nov 16, 2009 | popularity 4.5 / 5 (19) | comments 0

(PhysOrg.com) -- One of the drawbacks associated with using semiconductor lasers is that many of them can only produce a beam of a single wavelength, and can only send that beam in one direction at a time. ...


Fermi Telescope Peers Deep into Microquasar

Fermi Telescope Peers Deep into Microquasar (w/ Video)

Space & Earth / Astronomy

created Nov 27, 2009 | popularity 4.8 / 5 (17) | comments 0

(PhysOrg.com) -- NASA's Fermi Gamma-ray Space Telescope has made the first unambiguous detection of high-energy gamma-rays from an enigmatic binary system known as Cygnus X-3. The system pairs a hot, massive ...


A Tiny Cage of Gold Responds to Light, Opening to Empty Its Contents

Nanotechnology / Bio & Medicine

created Nov 19, 2009 | popularity 5 / 5 (3) | comments 0

(PhysOrg.com) -- Researchers at Washington University in St. Louis have developed a polymer-coated gold nanocage that not only opens in response to light to release a small amount of a drug payload, but then closes when the ...


Invisibility visualized: German team unveils new software for rendering cloaked objects

Invisibility visualized: German team unveils new software for rendering cloaked objects

Physics / Optics & Photonics

created Nov 13, 2009 | popularity 4 / 5 (5) | comments 1

(PhysOrg.com) -- Scientists and curiosity seekers who want to know what a partially or completely cloaked object would look like in real life can now get their wish -- virtually. A team of researchers at the ...


New nano color sorters from Molecular Foundry

New nano color sorters from Molecular Foundry

Nanotechnology / Nanophysics

created Nov 12, 2009 | popularity 4.3 / 5 (4) | comments 0

Berkeley Lab researchers have engineered a new class of bowtie-shaped devices that capture, filter and steer light at the nanoscale. These "nano-colorsorter" devices act as antennae to focus and sort light ...


'Dropouts' pinpoint earliest galaxies

'Dropouts' pinpoint earliest galaxies

Space & Earth / Astronomy

created Nov 06, 2009 | popularity 4.4 / 5 (13) | comments 15

Astronomers, conducting the broadest survey to date of galaxies from about 800 million years after the Big Bang, have found 22 early galaxies and confirmed the age of one by its characteristic hydrogen signature ...


Herschel takes a peek at the ingredients of the galaxies

Herschel takes a peek at the ingredients of the galaxies

Space & Earth / Astronomy

created Nov 27, 2009 | popularity 4.8 / 5 (9) | comments 1

(PhysOrg.com) -- The European Space Agency has today released spectacular new observations from the Herschel Space Observatory, including the UK-led SPIRE instrument. Spectrometers on board all three Hershel ...