This exam focus covers Exam Focus — Red Shift and Big Bang within Red Shift & Big Bang for GCSE Physics. Revise Red Shift & Big Bang in Space Physics for GCSE Physics with 13 exam-style questions and 12 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 12 of 14 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
🎯 Exam Focus — Red Shift and Big Bang
Examined in Edexcel 1PH0/1 (Paper 1). Edexcel includes more quantitative red-shift and Hubble's Law work at Higher tier than most other boards — expect calculation questions using v = H₀d alongside qualitative "explain" questions. Context-based: real galaxy spectra and redshift measurements.
Most Common Question Types
- Explain what red shift is and what it tells us about the universe [3-4 marks]
- State two pieces of evidence for the Big Bang [2 marks]
- Explain what the CMBR is and why it is evidence for the Big Bang [3 marks]
- Describe what happens to wavelength when a galaxy moves away [2 marks]
- Explain why more distant galaxies have greater red shift [2 marks]
What Examiners Want to See
For "explain what red shift tells us" questions, a full-mark answer needs: wavelength increases as galaxy moves away → this is red shift → more distant galaxies have greater red shift → so they are moving away faster → the universe is expanding. For CMBR, examiners want to see: it comes from all directions, it was predicted before discovery, and it is the cooled remnant of the early hot universe.
Practice questions for Red Shift & Big Bang
What is the orbital period of a geostationary satellite?
Explain why a geostationary satellite stays above the same point on Earth's surface.