IB Physics E.3 Radioactive Decay | Concept Tutorial | GradePod (HL)

This is the HL concept tutorial for E.3 Radioactive Decay in the current IB Physics syllabus. It's a long one because there's a lot to cover, and the HL content makes this topic significantly more demanding. We start with mass defect and binding energy before moving into decay types. Then we work through alpha, beta minus, beta plus and gamma decay in full, including the neutrino story, before finishing with half-life, the exponential decay equations, and background radiation. As you watch, tick off each learning objective on the free checklist on the GradePod page below. 👉 Free checklist + full topic page: https://www.gradepod.com/topics/e3-radioactive-decay It's a great way to track what you know and what still needs work. ━━━━━━━━━━━━━━━━━━━━━━━ WHAT'S COVERED IN THIS VIDEO ━━━━━━━━━━━━━━━━━━━━━━━ 0:00 Introduction: isotopes, nuclide notation and the stability graph 6:14 Mass defect: why a nucleus weighs less than the sum of its parts 7:55 Binding energy: definition and calculation using E = mc² 12:18 Binding energy per nucleon: the stability curve and what it tells us 17:34 Radioactive decay overview: the N vs Z stability graph 20:30 Strong nuclear force: what makes a nucleus stable or unstable 28:46 Decay types overview: alpha, beta and gamma 37:36 Alpha decay: writing and balancing nuclear equations 37:47 Beta minus decay and antineutrinos 41:33 Beta plus decay, positrons and neutrinos 42:53 Gamma radiation: properties and nuclear energy levels 50:31 Neutrinos: evidence from the continuous beta spectrum 52:20 Half-life: definition and graphical method 59:03 Decay constant and activity 63:40 Exponential decay equations: N = N₀e^(−λt) and A = A₀e^(−λt) 71:16 Background radiation: sources and how to correct count rates ━━━━━━━━━━━━━━━━━━━━━━━ WANT TO GO FURTHER? ━━━━━━━━━━━━━━━━━━━━━━━ The GradePod Exam Pack gives you everything you need to turn what you've just learned into marks: ✓ Revision note template (build your own notes as you watch, I reference it throughout this video) ✓ Knowledge questions for E.3 Radioactive Decay ✓ Topic-by-topic past paper questions with full mark schemes ✓ Full mock exam, annotated data booklet and Paper 1B practice One-time purchase. £39. Instant download. Every topic included. 👉 Get the Exam Pack: https://www.gradepod.com/exam-pack ━━━━━━━━━━━━━━━━━━━━━━━ NEXT STEP ━━━━━━━━━━━━━━━━━━━━━━━ Once you've watched this video and ticked off your checklist, your next step is the past paper walkthrough. Watch me work through real IB exam questions on Radioactive Decay, including the HL-only binding energy and neutrino questions: 👉 E.3 Radioactive Decay Past Paper Video (HL): https://www.youtube.com/watch?v=_KO9hMZmsRY ━━━━━━━━━━━━━━━━━━━━━━━ ABOUT GRADEPOD ━━━━━━━━━━━━━━━━━━━━━━━ I'm Sally Weatherly, IB Physics teacher since 2004, Fellow of the Institute of Physics, and founder of GradePod. I built GradePod for the students I couldn't reach in the classroom. Every tutorial is free. No login, no catch. 👉 All 24 topics, free: https://www.gradepod.com/topics ━━━━━━━━━━━━━━━━━━━━━━━ #IBPhysics #IBPhysicsRevision #GradePod #IB #IB2025 #IBPhysicsSL #IBPhysicsHL #RadioactiveDecay #BindingEnergy #HalfLife #NuclearPhysics #Radioactivity