Study Notes
Cosmology studies the origin and development of the Universe, primarily explained by the Big Bang Theory. This theory suggests the Universe began from a small, hot, dense point and has been expanding ever since.
- Big Bang Theory — The Universe started from a small, hot, dense point and expanded. Example: Like a balloon expanding with points on its surface representing galaxies.
- Galactic Red-Shift — Light from distant galaxies shifts towards the red end of the spectrum as they move away. Example: Observing redshift in light from distant galaxies indicates they are receding.
- Cosmic Microwave Background (CMB) Radiation — Remnant radiation from the early Universe, uniform across space. Example: CMB is detected as microwave radiation at a temperature of 2.73 K.
- Doppler Effect — Change in wavelength and frequency of waves from a moving source. Example: A siren's pitch changes as it moves past an observer.
Exam Tips
Key Definitions to Remember
- Big Bang Theory
- Galactic Red-Shift
- Cosmic Microwave Background Radiation
- Doppler Effect
Common Confusions
- Confusing redshift with blueshift
- Misunderstanding the uniformity of CMB radiation
Typical Exam Questions
- What is the Big Bang Theory? The Universe began from a small, hot, dense point and has been expanding.
- How does redshift support the Big Bang Theory? Redshift shows galaxies are moving away, indicating the Universe is expanding.
- What is the significance of CMB radiation? It is evidence of the early hot and dense state of the Universe.
What Examiners Usually Test
- Understanding of the Big Bang Theory and its evidence
- Ability to explain redshift and its implications
- Knowledge of the Doppler Effect and its application to light