electromagnetic radiation

Definitions of electromagnetic radiation
  1. noun
    radiation consisting of waves of energy associated with electric and magnetic fields resulting from the acceleration of an electric charge
    synonyms: electromagnetic wave, nonparticulate radiation
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    actinic radiation, actinic ray
    electromagnetic radiation that can produce photochemical reactions
    beam, electron beam, ray
    a group of nearly parallel lines of electromagnetic radiation
    black-body radiation, blackbody radiation
    the electromagnetic radiation that would be radiated from an ideal black body; the distribution of energy in the radiated spectrum of a black body depends only on temperature and is determined by Planck's radiation law
    Hertzian wave
    an electromagnetic wave generated by oscillations in an electric circuit
    gamma radiation, gamma ray
    electromagnetic radiation emitted during radioactive decay and having an extremely short wavelength
    a single frequency (or very narrow band) of radiation in a spectrum
    a short electromagnetic wave (longer than infrared but shorter than radio waves); used for radar and microwave ovens and for transmitting telephone, facsimile, video and data
    radio emission, radio radiation, radio wave
    an electromagnetic wave with a wavelength between 0.5 cm to 30,000 m
    X ray, X-radiation, X-ray, roentgen ray, x-ray
    electromagnetic radiation of short wavelength produced when high-speed electrons strike a solid target
    cathode ray
    a beam of electrons emitted by the cathode of an electrical discharge tube
    infrared, infrared emission, infrared light, infrared radiation
    electromagnetic radiation with wavelengths longer than visible light but shorter than radio waves
    light, visible light, visible radiation
    (physics) electromagnetic radiation that can produce a visual sensation
    particle beam
    a collimated flow of particles (atoms or electrons or molecules)
    sky wave
    a radio wave that is reflected back to earth by the ionosphere or a communications satellite; permits transmission around the curve of the earth's surface
    ground wave
    a radio wave propagated on or near the earth's surface
    radio signal
    a radio wave used to transmit and receive messages
    carrier, carrier wave
    a radio wave that can be modulated in order to transmit a signal
    short wave
    a radio wave with a wavelength less than 100 meters (a frequency greater than 3 megahertz)
    medium wave
    a radio wave with a wavelength between 100 and 1000 meters (a frequency between 300 kilohertz and 3000 kilohertz)
    long wave
    a radio wave with a wavelength longer than a kilometer (a frequency below 300 kilohertz)
    UV, ultraviolet, ultraviolet illumination, ultraviolet light, ultraviolet radiation
    radiation lying in the ultraviolet range; wave lengths shorter than light but longer than X rays
    type of:
    energy that is radiated or transmitted in the form of rays or waves or particles
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