| A | B |
|---|
| strong nuclear force | attractive force that acts between protons and neutrons in an atomic nucleus |
| radioactivity | process that occurs when a nucleus decays and emits alpha, beta, and gamma radiation |
| alpha particle | particle consisting of two protons and two neutrons that is emitted from a decaying atomic nucleus |
| transmutation | process of changing one element to another through radioactive decay |
| beta particle | electron that is emitted from a decaying atomic nucleus |
| gamma ray | electromagnetic wave with no mass and no charge that travels at the speed of light and is usually emitted with alpha or beta particles from a decaying atomic nucleus; has a wavelength less than about ten trillionths |
| half-life | amount of time it takes for half the nuclei in a sample of a radioactive isotope to decay |
| NaI scintillation detector | radiation detector |
| nuclear reactor | part of nuclear power plant where nuclear reactions take place |
| Geiger counter | radiation detector that produces a click or a flash of light when a charged particle is detected |
| nuclear fission | process of splitting an atomic nucleus into two or more nuclei with smaller masses |
| chain reaction | ongoing series of fission reactions |
| isotope | a version of an element with the same atomic number but different mass |
| nuclear fusion | reaction in which two or more atomic nuclei form a nucleus with a larger mass |
| radioactive dating | a way to use radioactive isotopes to find the age of fossils |
