A research team measures the same spectral line in the light from three galaxies. The table shows the increase in wavelength compared with the wavelength measured in a laboratory.
| Galaxy | Distance from Earth (million light-years) | Increase in wavelength (%) |
|---|---|---|
| A | 20 | 0.2 |
| B | 40 | 0.4 |
| C | 60 | 0.6 |
Explain what the measurements show and whether they rule out the Steady State theory.
94 exam-style questions on Edexcel GCSE Physics 7.2 The Universe and red-shift, covering 7.2.1 Big Bang and Steady State theories, 7.2.2 Evidence for the Big Bang, 7.2.3 The Doppler effect and red-shift, 7.2.4 Red-shift as evidence for an expanding Universe, and 7.2.5 The CMB and the accepted model. Each one has a worked solution and a mark scheme showing where the marks go.