Cosmology - OCR A Level Physics Revision Notes 2015

Key Topics Covered

This note summarizes important constants and equations related to cosmology, useful for OCR A Level Physics exam preparation. The original text provides limited detail; therefore, additional information is included here to enhance understanding.

Important Values and Constants

The following numeric constants and variables were listed in the original text, though their specific application within cosmological context is unclear without further information:

• Speed and Velocity (v, d): Fundamental concepts in physics, essential for understanding cosmological phenomena like the expansion of the universe.
• Equations of motion (X2, X1): Likely related to calculating distances or positions within cosmological models. More detail is needed to define their specific function.
• Significant numeric constants: These likely represent values related to cosmological parameters, though their exact meaning requires further research using relevant cosmological equations.
  • (6.74 \times 10^4)
  • (3.1 \times 10^{22})
  • (1H0) (Likely represents the Hubble constant, a crucial parameter in Hubble's Law).
  • (2.17 \times 10^{18})
  • (4.60 \times 10^{17})
  • (3.16 \times 10^7)

Core Cosmological Concepts

To supplement the limited information in the original text, here are key concepts in cosmology:

• Hubble's Law: Describes the relationship between the recessional velocity (v) of a galaxy and its distance (d) from us: v = H₀d, where H₀ is the Hubble constant. This law supports the idea of an expanding universe.

• Redshift: The stretching of light waves as they travel from distant galaxies towards us. The greater the redshift, the faster the galaxy is receding and the farther away it is. Redshift provides strong evidence for the Big Bang theory.

• Big Bang Theory: The prevailing cosmological model for the universe's origin and evolution. It posits that the universe originated from an extremely hot, dense state and has been expanding and cooling ever since.