{i} energy radiated in the form of waves or particles; process of emitting energy in electromagnetic waves or moving particles; act of emitting, act of beaming or glowing
a term with two broad meanings In the narrow sense, some type of electromagnetic wave: radio, microwave, light (infra-red, visible or ultra-violet), x-rays or gamma rays are all types of radiation Colloquially (the full term is "ionizing radiation") it means any spreading emission which can penetrate matter That includes x-rays and gamma rays, but also high-energy ions and electrons emitted by radioactive substances, accelerated by laboratory devices or encountered in space (e g the "radiation belt" and "cosmic radiation")
Energy in the form of electromagnetic waves or particles capable of damaging cells by removing electrons from atoms or molecules This damage can lead to cancer or other defects
Energy moving through space in the form of waves or particles Radiation can be ionizing, like alpha particles, beta particles, neutrons and X-rays, or non-ionizing, like visible light, heat, microwaves and radio waves Non-ionizing means that the energy level is too low to ionize the atoms
the process of heat transfer by means of infra-red radiatins, a form of electromagnetic wave Electromagnetic waves do not need any material medium for their propagation Space is almost completely empty, so the sun's heat cannot reach us by conduction or convection Because electromagnetic waves don't need a medium they are able to travel through space Anything above the temperature of absolute zero is able to emit and absorb infra-red radiations Radiation is absorbed by darker surfaces and reflected by lighter surfaces This is why people wearing darker clothing in the summer are hotter than thoose wearing white or light clothing Those wearing black will absorb the radiaions, therefore their temperature will rise
The process by which energy is propagated through any medium by virtue of the wave motion of that medium Electromagnetic radiation, which emits heat and light, is one form Sound waves are another
Radiation is energy, especially heat, that comes from a particular source. The satellite will study energy radiation from stars. Process by which energy is emitted from a source and propagated through the surrounding medium, or the energy involved in this process. Radiation consists of a flow of atomic or subatomic particles or of waves. Familiar examples are light (a form of electromagnetic radiation) and sound (a form of acoustic radiation). Both electromagnetic and acoustic radiation can be described as waves with a range of frequencies and intensities. Electromagnetic radiation is also often treated as discrete packets of energy, called photons. All matter is constantly bombarded by radiation from cosmic and terrestrial sources, and radioactive elements emit several types of radiation (see radioactivity). See also Cherenkov ratiation, Hawking radiation, infrared radiation, synchrotron radiation, thermal radiation, ultraviolet radiation. braking radiation Cherenkov radiation cosmic background radiation electromagnetic radiation Hawking radiation infrared radiation enhanced radiation warhead radiation injury radiation pressure radiation therapy synchrotron radiation thermal radiation ultraviolet radiation Van Allen radiation belts
the act of spreading outward from a central source a radial arrangement of nerve fibers connecting different parts of the brain the spread of a group of organisms into new habitats energy that is radiated or transmitted in the form of rays or waves or particles the spontaneous emission of a stream of particles or electromagnetic rays in nuclear decay
The emission of very fast atomic particles or rays by nuclei Some elements are naturally radioactive while others become radioactive after bombardment with neutrons or other particles The three major forms of radiation are alpha, beta, and gamma, named for the first three letters of the Greek alphabet
The transmission of energy through electromagnetic radiation; a method of transmitting energy through a vacuum Radiation is composed of particles of energy called photons The other two methods of transfering energy are convection and conduction
syndrome resulting from exposure to ionizing radiation (e g , exposure to radioactive chemicals or to nuclear explosions); low doses cause diarrhea and nausea and vomiting and sometimes loss of hair; greater exposure can cause sterility and cataracts and some forms of cancer and other diseases; severe exposure can cause death within hours; "he was suffering from radiation"
1 The process by which electromagnetic energy is propagated through free space by virtue of joint undulatory variations in the electric and magnetic fields in space This concept is to be distinguished from conduction and convection A group of physical principles known as the radiation laws comprise, to a large extent, the current state of practical knowledge of the complex radiative processes
The process of emitting: energy waves, such as heat and light from the sun to the earth or heat from the earth to space; particles of matter from the disintegration of the nuclei of atoms, such as gamma rays
the propagation of energy; for the purposes of this text primarily restricted to the propagation of acoustic energy through a medium [as opposed to electronic radiation (such as light, electricity, radio waves, etc ), which does not require a medium] Although primarily propagated by the vibration of a solid surface, acoustic radiation can also be generated by other means (see text)
Radiation consists of very small particles of a radioactive substance. Large amounts of radiation can cause illness and death. They suffer from health problems and fear the long term effects of radiation
in the context of the RReDC, synonymous with electromagnetic radiation, or the energy produced by an oscillating electrical (and magnetic) field, transmitted by photons See Electromagnetic Spectrum
Radiation is energy in transit in the form of high speed particles and electromagnetic waves Radiation is further defined into ionizing and non-ionizing radiation Ionizing radiation is radiation with enough energy so that during an interaction with an atom, it can remove tightly bound electrons from their orbits, causing the atom to become charged or ionized Examples are X-rays and electrons Non-ionizing radiation is radiation without enough energy to remove tightly bound electrons from their orbits around atoms Examples are microwaves and visible light