electromagnetic radiation(redirected from E. M. radiation)
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Related to E. M. radiation: electromagnetic radiation
Energy having both the form of electromagnetic waves and the form of a stream of photons and traveling at the speed of light in a vacuum. The entire range of frequencies and wavelengths of electromagnetic radiation makes up the electromagnetic spectrum.
(General Physics) radiation consisting of self-sustaining oscillating electric and magnetic fields at right angles to each other and to the direction of propagation. It does not require a supporting medium and travels through empty space at the speed of light. See also photon
radiation consisting of electromagnetic waves, including radio waves, infrared, visible light, ultraviolet, x-rays, and gamma rays.
Energy that moves through space and matter both in the form of magnetic and electric waves and in the form of a stream of particles called photons.
Did You Know? Many people have heard that light is made up of waves, but what does that mean? The answer seems very abstract: light, and other forms of electromagnetic radiation, are made up of wave-shaped electric and magnetic fields that reinforce each other as they travel together. In the 19th century, physicists discovered that a changing electric field can create a magnetic field, and a changing magnetic field can create an electric field. So a wave-shaped electric field (for example, the field created when a charged particle such as an electron moves up and down) can create a wave-shaped magnetic field, which in turn reproduces the wave-shaped electric field. These mutually re-creating fields travel at the speed of light. Electromagnetic radiation can have a variety of properties, depending on its wavelength. Certain wavelengths make up the spectrum of visible light. Infrared light and radio waves have longer wavelengths, whereas ultraviolet light, x-rays, and gamma rays have shorter wavelengths. These wave properties do not tell the full story of electromagnetic radiation, however. Visible light and other forms of electromagnetic radiation also exist as streams of the particles known as photons. The energy of the photons increases as the frequency of the waves gets higher.
Radiation made up of oscillating electric and magnetic fields and propagated with the speed of light. Includes gamma radiation, X-rays, ultraviolet, visible, and infrared radiation, and radar and radio waves.
Waves of energy associated with electric and magnetic fields.
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|Noun||1.||electromagnetic radiation - radiation consisting of waves of energy associated with electric and magnetic fields resulting from the acceleration of an electric charge|
photon - a quantum of electromagnetic radiation; an elementary particle that is its own antiparticle
blackbody radiation, black-body 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
line - a single frequency (or very narrow band) of radiation in a spectrum
microwave - 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
radiation - energy that is radiated or transmitted in the form of rays or waves or particles
radio emission, radio radiation, radio wave - an electromagnetic wave with a wavelength between 0.5 cm to 30,000 m