| A | B |
|---|
| electrons | a negatively charged particle located outside the nucleus of an atom |
| radiation | any form of energy given off by an object |
| radioactivity | the release of high energy particles by radioactive elements |
| beta particle | a high speed electron given off by a radioactive substance |
| alpha particle | a positively charged particle given off by a radioactive substance |
| gamma rays | electromagnetic radiation with a shorter wavelength than x-rays |
| nucleus | dense positively charged center of an atom |
| proton | positively charged particle located in the nucleus of an atom |
| neutron | a particle with no charge located in the nucleus of an atom |
| quark | smaller particles into which protons and neutrons can be split |
