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  1. Radioactivity | Definition, Types, Applications, & Facts | Britannica

    Dec 6, 2025 · Radioactivity, property exhibited by certain types of matter of emitting energy and subatomic particles spontaneously. It is, in essence, an attribute of individual atomic nuclei.

  2. Radioactive decay - Wikipedia

    Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by …

  3. What Is Radioactivity? - Energy.gov

    As its name implies, radioactivity is the act of emitting radiation spontaneously. This is done by an atomic nucleus that, for some reason, is unstable; it "wants" to give up some energy in order to …

  4. Radioactivity: Definition, Types, Formula, and Applications

    Jun 10, 2025 · Radioactivity occurs when an atom has an excess of energy, mass, or both, making its nucleus unstable. To reach a lower, more stable energy level, it releases energy in …

  5. Radioactivity and the Types of Radioactive Decay

    May 30, 2021 · Radioactivity is the spontaneous emission of ionizing radiation from nuclear decay and reactions. The three main types of radioactive decay are alpha, beta, and gamma decay, …

  6. The Science Behind Radioactive Elements

    May 1, 2025 · This article will take you through the depths of atomic structure, the mechanics of radioactivity, the different types of decay, the history of its discovery, the technological and …

  7. Radioactivity - HyperPhysics

    Radioactive decay rates are normally stated in terms of their half-lives, and the half-life of a given nuclear species is related to its radiation risk. The different types of radioactivity lead to …

  8. Radiation Basics | Nuclear Regulatory Commission

    These forces within the atom work toward a strong, stable balance by getting rid of excess atomic energy (radioactivity). In that process, unstable nuclei may emit a quantity of energy, and this …

  9. What Is Radioactivity: Simple Definition, Explanation And Examples

    Jun 2, 2024 · This property of turning into something new to attain stability is what we call radioactivity, and the process by which it transforms is called radioactive decay.

  10. Radiation in Everyday Life - International Atomic Energy Agency

    Radioactivity is the term used to describe disintegration of atoms. The atom can be characterized by the number of protons in the nucleus. Some natural elements are unstable. Therefore, their …