This definitions covers Key Definitions within Radioactive Decay for GCSE Physics. Revise Radioactive Decay in Atomic Structure for GCSE Physics with 15 exam-style questions and 6 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 8 of 14 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
📖 Key Definitions
Radioactive decay: The spontaneous, random emission of radiation from an unstable nucleus as it becomes more stable.
Alpha particle (α): A particle consisting of 2 protons and 2 neutrons, emitted from heavy unstable nuclei.
Beta particle (β): A high-speed electron emitted from the nucleus when a neutron converts to a proton.
Gamma ray (γ): High-energy electromagnetic radiation emitted from a nucleus releasing excess energy.
Ionisation: The process of removing electrons from atoms, creating ions. Radiation causes ionisation as it passes through matter.
Practice questions for Radioactive Decay
An alpha particle consists of which particles?
Explain why alpha radiation is described as highly ionising but weakly penetrating.