GEN NOTES FROM PPs

• Compare how radio and gamma rays are produced.

  Radio waves are produced intentionally. Gamma rays are produced unintentionally.

  Radio waves may be produced in electrical circuits. Gamma rays may be produced to stabilise a nucleus.
• What does the eyepiece do in a telescope?

  Magnify an image.
• What is the difference between heliocentric and geocentric?

  Geocentric- Earth being at the center of the universe, with planets orbiting it

  Heliocentric- sun is at the center with the planets orbiting it
• Why in a radioactivity test would results be scattered?

  Radioactive decay is unreliable/random, results therefore are inconistent
• Arguments against using nuclear power-

  bomb making

  no good place to store waste

  nuclear disasters
• Arguments for using nuclear power?

  it is 'clean energy' - no carbon emissions

  high energy output

  cheap running costs
• Float

  Less dense than water
• Order of planets

  • Mercury
  • Venus
  • Earth
  • Mars
  • Jupiter
  • Saturn
  • Uranus
  • Neptune
• Red shift


  • Light appears in red shifted galaxies moving away from Earth
  • Wavelength appears higher and frequency appears lower than reality
• Red shift shows that the universe is expanding
• Therefore the universe must have been formed from a single point
• CMB proves that the universe has cooled and expanded since its beginning
• Big Bang theory


  Began from a small, dense space that exploded, and the expansion from this is ongoing
• Steady State theory


  Universe has always existed as it is now, and it will stay the same