أرشيف الوسم : radiation

absorption spectrum a spectrum produced when electromagnetic radiation is absorbed by a sample. The frequencies of the radiation absorbed are those able to excite the atoms or molecules of the sample from their ground states to excited states. The frequency, ν, at which a particular absorption line occurs depends on …

Low inten­sity ionizing radiation present on the surface of the earth and in the atmosphere as a result of cosmic radiation and the presence of radio­isotopes in the earth’s rocks, soil, and atmosphere. The radioisotopes are either natural or the result of nu­clear fallout or waste gas from power stations. …