Electromagnetic Radiation

Definition: Electromagnetic Radiation

Electromagnetic Radiation

Noun

1. Radiation consisting of waves of energy associated with electric and magnetic fields resulting from the acceleration of an electric charge.

Specialty Definitions: Electromagnetic Radiation

Domain	Definitions
Aerospace	Energy propagated through space or through material media in the form of an advancing disturbance in electric and magnetic fields existing in space or in the media. The term radiation , alone, is used commonly for this type of energy, although it actually has a broader meaning. Also called electromagnetic energy or simply radiation. See electromagnetic spectrum. (references)
Electrical Engineering	The emission and propagation through space or through a material medium of energy in the form of electromagnetic waves. Source: European Union. (references)
Energy	A traveling wave motion resulting from changing electric or magnetic fields. Familiar electromagnetic radiation range from x-rays (and gamma rays) of short wavelength, through the ultraviolet, visible, and infrared regions, to radar and radio waves of relatively long wave length. (references)
Physics	Radiation that travels through vacuous space at the speed of light and propagates by the interplay of oscillating electric and magnetic fields. This radiation has a wavelength and a frequency. (references)
Science	Energy propagated as time-varying electric and magnetic fields. These two fields are inextricably linked as a single entity since time-varying electric fields produce time-varying magnetic fields and vice versa. Light and radar are examples of electromagnetic radiation differing only in their wavelengths (or frequency). Electric and magnetic fields propagate through space at the speed of light. (references)
	Energy that travels through space in the form of a wave. The Sun's energy is electromagnetic radiation. (references)
Solar	The energy produced by an oscillating electrical (and magnetic) field, transmitted by photons. See Electromagnetic Spectrum. (references)
Source: compiled by the editor from various references; see credits.

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Specialty Definition: Electromagnetic radiation

(From Wikipedia, the free Encyclopedia)

Electromagnetic radiation is a combination of oscillating electric and magnetic fields propagating through space and carrying energy from one place to another. Light is a form of electromagnetic radiation. The theoretical study of electromagnetic radiation is called electrodynamics, a subfield of electromagnetism.

Any electric charge which accelerates radiates electromagnetic radiation. When any wire (or other conducting object such as an antenna) conducts alternating current, electromagnetic radiation is propagated at the same frequency as the electric current. Depending on the circumstances, it may behave as waves or as particles. As a wave, it is characterized by a velocity (the velocity of light), wavelength, and frequency. When considered as particles, they are known as photons, and each has an energy related to the frequency of the wave given by Planck's relation E = hv, where E is the energy of the photon, h is Planck's constant - 6.626 × 10^-34 J·s - and v is the frequency of the wave. Einstein later updated this formula to E_photon = hv.

Generally, electromagnetic radiation is classified by wavelength into radio, microwave, infrared light, visible light, ultraviolet light, X-rays and gamma rays. The details of this classification are contained in the article on the electromagnetic spectrum.

The effect of radiation depends on the amount of energy per quantum it carries. High energies correspond to high frequencies and short wavelengths, and vice versa. One rule is always obeyed, regardless of the circumstances. Radiation in vacuum always travels at the speed of light, relative to the observer, regardless of the observer's velocity. (This observation led to Albert Einstein's development of the theory of special relativity).

Much information about the physical properties of an object can be obtained from its electromagnetic spectrum; this can be either the spectrum of light emitted from, or transmitted through the object. This involves spectroscopy and is widely used in astrophysics. For example; many hydrogen atoms emit radio waves which have a wavelength of 21.12 cm.

When electromagnetic radiation passes through a conductor it induces an electric current flow in the conductor. This effect is used in antennas. Electromagnetic radiation may also cause certain molecules to oscillate and thus to heat up; this is exploited in microwave ovens.

Synonyms: Electromagnetic Radiation

Synonyms: electromagnetic wave (n), nonparticulate radiation (n). (additional references)

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Crosswords: Electromagnetic Radiation

English words defined with "electromagnetic radiation": A, absorptance, absorption coefficient, absorption spectrum, actinic radiation, actinic ray, actinometer, actinometry, action spectrum, angstrom, angstrom unit, astronomical telescope ♦ beam, black body, blackbody, black-body radiation ♦ coefficient of absorption ♦ diffraction grating, duality ♦ electron beam, electronic jamming, emission spectrum ♦ full radiator ♦ gamma radiation, gamma ray, glow, glowing, grating ♦ homochromatic ♦ infrared, infrared emission, infrared frequency, infrared light, infrared radiation, infrared , intensity, intensity level ♦ jam, jamming ♦ klystron ♦ light, light unit, Lodge ♦ monochromatic ♦ opacity ♦ photoconduction, photoconductivity, photon, polychromatic ♦ radiance, ray, resonance, roentgen ray ♦ Sir Oliver Joseph Lodge, Sir Oliver Lodge, source of illumination, strength ♦ transparence, transparency ♦ visible light, visible radiation ♦ wave-particle duality ♦ X ray, X-radiation. (references)

Specialty definitions using "electromagnetic radiation": absorption line, Advanced Very High Resolution Radiometer, angle of arrival, anomalous dispersion, ATOMIC-ABSORPTION SPECTROPHOTOMETRY ♦ Black body radiation, bremsstrahlung, bremsstrahlung effect ♦ Cerenkov radiation, cloud absorption, collecting area, continuous spectrum, Cosmic radiation, cyclotron radiation ♦ deceleration radiation ♦ electromagnetic energy, electromagnetic radiation hazard, electromagnetic theory, electronic eavesdropping, EMISSION SPECTROGRAPHY, EMR ♦ far infrared, Fermat principle, FLUORIMETRY ♦ Gamma Rays, gamma-rays, gray body ♦ heat transfer, Huygens principle, Huygen's principle ♦ Infra-red radiation, interception of electronic impulses ♦ light-year, line spectra ♦ magnetic disturbance daily variation, magnetic solar daily variation, magnetoionic theory, middle infrared, Mie theory, monochromatic light, MPR II ♦ near infrared, nonionising radiation, non-ionising radiation, Non-ionizing Electromagnetic Radiation, nonionizing radiation, non-ionizing radiation, nuclear radiation ♦ opaque plasma, optical coupler, optical fiber coupler, optical fibre coupler, Optical Radiation, Oxidants, Photochemical ♦ photoelectric effect, photon engine, photosynthetically active radiation, Photovoltaic and solar thermal energy, Planck constant, PLANCK'S, Plasma Window, pyron ♦ röntgen rays, Radiation, Ionizing, Radiation, Nonionizing, radiative transfer, radio energy, Radio Frequency Radiation, radio waves, radiofrequency, RADIOMETRIC, radiospectrum, reflected ray, Re-radiation, roentgen rays ♦ Scattering, Radiation, Secondary radiation, selective absorption, Shortwave Radiation, short-wave radiation, Spectral Line, spurious radiation ♦ Terrestrial Radiation, thermal infrared, thermal radiation, Thomson scattering ♦ Ultraviolet Therapy ♦ velocity of propagation ♦ Weston photronic cell ♦ X-rays. (references)

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Commercial Usage: Electromagnetic Radiation

Domain	Title
Books	An Introduction to Classical Electromagnetic Radiation (reference) Atomic, Molecular, and Optical Physics: Electromagnetic Radiation (Experimental Methods in the Physical Sciences, Vol 29C) (reference) Biological effects of electromagnetic radiation (reference) Classical Electromagnetic Radiation (reference) Condensation of Supersaturated Vapor in a Field of Electromagnetic Radiation (Soviet Technology Reviews Series, Section B) (reference) (more book examples)

Periodicals	Biological Effects Of Nonionizing Electromagnetic Radiation Digest Update (reference) (more periodical examples)
Source: compiled by the editor from various references; see credits.

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Expression: Electromagnetic Radiation

Expression using "electromagnetic radiation": electromagnetic radiation hazard. Additional references.
Source: compiled by the editor from various references; see credits.

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Frequency of Internet Keywords: Electromagnetic Radiation

The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com.

Expression	Frequency per Day
electromagnetic radiation	67
danger electromagnetic radiation	4
Source: compiled by the editor from various references; see credits.

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Modern Translations: Electromagnetic Radiation

Language		Translations for "electromagnetic radiation"; alternative meanings/domain in parentheses.
Danish		elektromagnetisk stråling (EM radiation, radiation EM). (various references)

Dutch		elektromagnetische straling (EM radiation, radiation EM). (various references)

Finnish		sähkömagneettinen säteily (EM radiation, radiation EM). (various references)

French		rayonnement EM, radiation électromagnétique. (various references)

German		EM-Strahlung (EM radiation, radiation EM), EMR, elektromagnetische Strahlung (EM radiation, radiation EM), elektromagnetische Strahlen (EM radiation, radiation EM), elektromagnetische Reflexion. (various references)

Greek		ηλεκτρομαγνητική ακτινοβολία (EM radiation, radiation EM). (various references)

Hungarian		elektromágneses sugárveszély (electromagnetic radiation hazard). (various references)

Italian		radiazione EM (EM radiation, radiation EM), radiazione elettromagnetica (EM radiation, radiation EM). (various references)

Pig Latin		electromagneticay adiationray.(various references)

Portuguese		radiacao electromagnetica (EM radiation, radiation EM), campo eletromagnético. (various references)

Serbo-Croatian		elektormagnetske radijacione smetnje (electromagnetic radiation hazard). (various references)

Spanish		radiación electromagnética (EM radiation, radiation EM). (various references)

Swedish		elektromagnetisk strålning (EM radiation, radiation EM). (various references)
Source: compiled by the editor from various translation references.

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Misspellings: Electromagnetic Radiation

Misspellings
	"Electromagnetic Radiation" is suggested in spellcheckers for the following: electromagnetic radition. (additional references)
Source: compiled by the editor, based on several corpora (additional references).

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