IB Diploma · Physics · Chapter 24

Ch 24 E.5 Fusion and stars: complete notes

Neat, exam-ready notebook-style notes for Ch 24 E.5 Fusion and stars, following the IB Diploma syllabus, SL and HL. This chapter is part of the complete Physics Notes for IB Diploma Students (SL and HL): All 24 Topics.

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Free preview: Ch 24 E.5 Fusion and stars notes

A quick look at the chapter from our IB Diploma Physics notes. The full chapter notes have the detailed explanations, diagrams and practice questions with answers.

Topics in this chapter

1. What you must be able to do
2. Why stars are stable
3. Fusion: the energy source
4. Stellar evolution
5. The Hertzsprung–Russell (HR) diagram
6. Luminosity, temperature and radius
7. Stellar parallax and distance units

“I can” checklist: what you must be able to do

• I can explain stellar equilibrium, and the conditions needed for fusion.
• I can calculate the energy released in a fusion reaction and the rate of fusion in a star.
• I can describe how a star's mass decides its evolution and end state.
• I can sketch and interpret an HR diagram, including lines of constant radius.
• I can use parallax to find distances, and convert between AU, ly and pc.
• I can find a star's radius from its luminosity and surface temperature, and its temperature from its spectrum.

What is inside the full chapter notes

• Concept notes with 8 worked examples
• Figures: equilibrium, HR diagram, parallax
• Common mistakes; investigation (IA) ideas
• 15 Paper 1A-style MCQs, explained
• 3 Paper 2-style structured questions with mark schemes, plus a data-based question
• Quick-reference sheet and "I can" checklist

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What you get in the pack

• All 24 topics of IB Diploma Physics for students taking Standard Level or Higher Level (first assessment 2025): kinematics, forces and momentum, work, energy and power, rigid body mechanics, special relativity, thermal energy transfers, the greenhouse effect, gas laws, thermodynamics, current and circuits, simple harmonic motion, the wave model, wave phenomena, standing waves, the Doppler effect, gravitational, electric and magnetic fields, induction, atomic structure, quantum physics, radioactive decay, fission, fusion and stars
• Every syllabus statement covered in order, each marked SL or HL, with clear notes, tables and diagrams drawn for these notes
• Worked examples in every topic: calculations and model answers that show how to earn the marks
• Original Paper 1A-style multiple-choice questions with explained answers, plus Paper 2-style structured and data-based questions with full mark schemes (no past-paper reprints)
• Common mistakes and investigation (internal assessment) ideas for every topic
• Quick-reference sheet and an "I can" checklist at the end of every topic
• Colour PDF and a black and white copy of every chapter for printing
• Independent notes for IB Diploma students; not endorsed by or affiliated with the International Baccalaureate Organization (IBO)

All chapters in this pack

1. Ch 1 A.1 Kinematics
2. Ch 2 A.2 Forces and momentum
3. Ch 3 A.3 Work, energy and power
4. Ch 4 A.4 Rigid body mechanics
5. Ch 5 A.5 Galilean and special relativity
6. Ch 6 B.1 Thermal energy transfers
7. Ch 7 B.2 Greenhouse effect
8. Ch 8 B.3 Gas laws
9. Ch 9 B.4 Thermodynamics
10. Ch 10 B.5 Current and circuits
11. Ch 11 C.1 Simple harmonic motion
12. Ch 12 C.2 Wave model
13. Ch 13 C.3 Wave phenomena
14. Ch 14 C.4 Standing waves and resonance
15. Ch 15 C.5 Doppler effect
16. Ch 16 D.1 Gravitational fields
17. Ch 17 D.2 Electric and magnetic fields
18. Ch 18 D.3 Motion in electromagnetic fields
19. Ch 19 D.4 Induction
20. Ch 20 E.1 Structure of the atom
21. Ch 21 E.2 Quantum physics
22. Ch 22 E.3 Radioactive decay
23. Ch 23 E.4 Fission
24. Ch 24 E.5 Fusion and stars