This deep dive covers The Three Types of Radiation within Radioactive Decay for GCSE Physics. Revise Radioactive Decay in Atomic Structure for GCSE Physics with 13 exam-style questions and 6 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 2 of 14 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 2 of 14
Practice
13 questions
Recall
6 flashcards
🔬 The Three Types of Radiation
There are three main types of nuclear radiation, each with very different properties. They differ in what they are made of, how far they travel, and how much they ionise surrounding material.
Alpha (α) particles are the largest — they consist of 2 protons and 2 neutrons (identical to a helium-4 nucleus). Because they are large and carry a +2 charge, they interact heavily with surrounding atoms, losing energy quickly. This makes them the most ionising but least penetrating type.
Beta (β) particles are high-speed electrons emitted from the nucleus when a neutron turns into a proton. They are much smaller and faster than alpha particles, so they travel further and are less ionising.
Gamma (γ) rays are electromagnetic radiation — high-energy photons with no mass and no charge. They pass through most materials easily, making them the most penetrating and least ionising type.
Quick Check: Which type of radiation is most ionising and why?
Alpha radiation is most ionising because it is large, has a +2 charge, and interacts heavily with surrounding atoms, stripping electrons and losing energy quickly.