Understudy definition, to learn (a role) in order to replace the regular actor or actress when necessary. See more.
Radiation. radiation. (Science: radiobiology) propagation of energy through space. In the context of this report, it is electromagnetic radiation (x-rays or gamma rays) or corpuscular radiation (alpha particles, electrons, protons, neutrons) capable of producing ionisation.adiation. radiation. (Science: radiobiology) propagation of energy through space. In the context of this report, it is electromagnetic radiation (x-rays or gamma rays) or corpuscular radiation (alpha particles, electrons, protons, neutrons) capable of producing ionisation.
'Radioactivity' is the energy and mass released by spontaneous changes in the nucleus of an atom. However, 'Radiation' is energy that travels ('radiates') as waves or particles. Heat, light, sound, microwaves, radar, radio waves, X-rays, alpha and beta particles, and gamma rays are all forms of radiation.