A spectral line has a wavelength of 500 nm when measured in a laboratory. Astronomers measure the wavelength of the same line in light from three galaxies.
| Galaxy | Distance from Earth (million light-years) | Observed wavelength (nm) |
|---|---|---|
| A | 140 | 505 |
| B | 280 | 510 |
| C | 420 | 515 |
Compare the observed wavelengths from the three galaxies. Include a quantitative comparison using the data.
Explain how these observations support the Big Bang theory.
79 exam-style questions on AQA GCSE Physics 8.2 Red-shift, covering 8.2 Red-shift. Each one has a worked solution and a mark scheme showing where the marks go.