Home/Glossary/BecquerelBBecquerelNuclear EnergySI unit of activity.One becquerel equals one nuclear decay per second.Keep exploringArticlesIonising RadiationIonizing radiation can be classified into alpha, beta, gamma, X-rays, and neutrons, while cosmic radiation is composed primarily of high-energy protons.4 min readGlossaryRRadioactivitySpontaneous nuclear decay.