8(c) Stellar evolution
Pearson Edexcel International GCSE Physics · 4PH1
Paper 1 | Whole paper: Core content, all eight topics
How stars form, what keeps them stable, and the two very different endings determined by mass.
Specification coverage
Topic 8 Astrophysics (c) Stellar evolution — statements 8.9–8.14
Assessment objectives: AO1, AO2. Suggested learning time: 70 minutes.
Required knowledge
- The life cycle of a star from nebula to main sequence
- The balance between gravitational collapse and radiation pressure in a stable star
- The evolution of stars of similar mass to the Sun: red giant, white dwarf
- The evolution of stars much more massive than the Sun: red supergiant, supernova, neutron star or black hole
- The classification of stars by colour and surface temperature
Required skills
- Explain a stage of stellar evolution in terms of the forces acting
- Compare the fates of low-mass and high-mass stars
How it is examined
- Multiple-choice and short-answer recall
- Calculations using the specification's relationships
- Extended open-response applying the physics to an unfamiliar situation
Common mistakes
- Giving the same ending for every star. Mass determines the fate, and the specification requires both routes.
- Saying a star 'burns' fuel. It fuses nuclei; combustion is a different process entirely.
- Describing a stable star as one where nothing is happening. It is a balance between two enormous opposing effects.