The Sun as a star
Cambridge IGCSE Physics (0625) · Unit 6: Space physics · 4 flashcards
The Sun as a star is topic 6.2.1 in the Cambridge IGCSE Physics (0625) syllabus , positioned in Unit 6 — Space physics , alongside The Earth, The Solar System and Stars. In one line: The two most abundant elements in the Sun are hydrogen and helium. These elements undergo nuclear fusion, releasing vast amounts of energy.
This topic is examined in Paper 1 (multiple-choice) and Papers 3/4 (theory), plus Paper 5 or Paper 6 (practical / alternative to practical).
The deck below contains 4 flashcards — 1 definition — covering the precise wording mark schemes reward. Use the definition card to lock down command-word answers (define, state), then move on to the concept and application cards to handle explain, describe and compare questions.
The two most abundant elements that make up the Sun
The two most abundant elements in the Sun are hydrogen and helium. These elements undergo nuclear fusion, releasing vast amounts of energy.
What the Cambridge 0625 syllabus says
2026-2028 syllabus, in our wordsWhat the syllabus expects you to be able to do in this topic, in plain English. Match the command word (Describe, Explain, State, etc.) in your answer to score full marks. For the exact wording, see the official syllabus (PDF).
- Know Know that the Sun is a medium-sized star composed mainly of hydrogen and helium. Know also that most of the energy it radiates lies in three parts of the electromagnetic spectrum: ultraviolet, visible light and infrared.
- Know Know that nuclear reactions releasing energy are what power stars, and that in a stable star these reactions fuse hydrogen into helium. Supplement
What are the two most abundant elements that make up the Sun?
The two most abundant elements in the Sun are hydrogen and helium. These elements undergo nuclear fusion, releasing vast amounts of energy.
Describe the regions of the electromagnetic spectrum in which the Sun radiates most of its energy.
The Sun radiates most of its energy in the infrared, visible light, and ultraviolet regions of the electromagnetic spectrum. Infrared radiation is felt as heat, visible light allows us to see, and ultraviolet radiation can cause sunburn.
Explain how the Sun, a stable star, generates its energy. Include the names of the elements involved in the primary nuclear reaction.
The Sun generates energy through nuclear fusion in its core. Specifically, hydrogen nuclei (protons) fuse together to form helium nuclei. This fusion process releases a tremendous amount of energy in the form of electromagnetic radiation and kinetic energy of the particles. The energy released balances the gravitational forces, creating a stable star.
State the name of the nuclear process that powers the Sun and describe the particles that combine to form helium.
The nuclear process is called nuclear fusion. Four hydrogen nuclei (protons) combine in a series of steps to form one helium nucleus.
Key Questions: The Sun as a star
What are the two most abundant elements that make up the Sun?
The two most abundant elements in the Sun are hydrogen and helium. These elements undergo nuclear fusion, releasing vast amounts of energy.
More topics in Unit 6 — Space physics
The Sun as a star sits alongside these Physics decks in the same syllabus unit. Each uses the same spaced-repetition system, so progress in one informs the next.
Key terms covered in this The Sun as a star deck
Every term below is defined in the flashcards above. Use the list as a quick recall test before your exam — if you can't define one of these in your own words, flip back to that card.
Related Physics guides
Long-read articles that go beyond the deck — cover the whole subject's common mistakes, high-yield content and revision pacing.
How to study this The Sun as a star deck
Start in Study Mode, attempt each card before flipping, then rate Hard, Okay or Easy. Cards you rate Hard come back within a day; cards you rate Easy push out to weeks. Your progress is saved in your browser, so come back daily for 5–10 minute reviews until every card reads Mastered.
Study Mode
Space to flip • ←→ to navigate • Esc to close
You're on a roll!
You've viewed 10 topics today
Create a free account to unlock unlimited access to all revision notes, flashcards, and study materials.
You're all set!
Enjoy unlimited access to all study materials.
Something went wrong. Please try again.
What you'll get:
- Unlimited revision notes & flashcards
- Track your study progress
- No spam, just study updates