Study Notes
Red shift is a phenomenon that provides evidence for the expansion of the universe, supporting the Big Bang Theory.
- Redshift — the increase in wavelength of light from an object moving away from the observer. Example: Light from distant galaxies appears redder.
- Blueshift — the decrease in wavelength of light from an object moving towards the observer. Example: Light from objects moving closer appears bluer.
- Doppler Effect — change in frequency or wavelength of a wave in relation to an observer moving relative to the wave source. Example: The change in pitch of a passing siren.
Exam Tips
Key Definitions to Remember
- Redshift
- Blueshift
- Doppler Effect
Common Confusions
- Confusing redshift with blueshift
- Misunderstanding that redshift means objects are moving away, not towards
Typical Exam Questions
- What is redshift? Redshift is the increase in wavelength of light from an object moving away from the observer.
- How does redshift support the Big Bang Theory? Redshift indicates that galaxies are moving away from us, suggesting the universe is expanding.
- What is the Doppler Effect? The Doppler Effect is the change in frequency or wavelength of a wave in relation to an observer moving relative to the wave source.
What Examiners Usually Test
- Understanding of redshift and its implications for the expanding universe
- Ability to explain the Doppler Effect in terms of light and sound
- Application of redshift to support the Big Bang Theory