The table shows results for distant galaxies. Mpc is a unit of distance.
| Distance in Mpc | Recession speed in km/s |
|---|---|
| 20 | 1400 |
| 40 | 2800 |
| 60 | 4200 |
A fourth galaxy follows the same relationship and recedes at 3500 km/s.
What is its distance?
30 Mpc30\ \mathrm{Mpc}30 Mpc
50 Mpc50\ \mathrm{Mpc}50 Mpc
70 Mpc70\ \mathrm{Mpc}70 Mpc
90 Mpc90\ \mathrm{Mpc}90 Mpc
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.