Measurements are taken near the end of the life of a star with a similar mass to the Sun.
| Observation | Result |
|---|---|
| motion of the outer layers | moving away from the remaining object |
| mass of the remaining object | 1.0 × 1030 kg |
| volume of the remaining object | 1.3 × 1021 m3 |
| energy released by nuclear fusion in 1 s | 0 J |
Calculate the mean density of the remaining object.
Use the information and your answer to (a) to name the remaining object.
Explain why the remaining object continues to shine when no energy is released by nuclear fusion, and predict what happens to its brightness over billions of years.
75 exam-style questions on Edexcel GCSE Physics 7.3 Stars, covering 7.3.1 Evolution of stars similar to the Sun, 7.3.2 Evolution of massive stars, and 7.3.3 Observing the Universe. Each one has a worked solution and a mark scheme showing where the marks go.