AQA GCSE Physics 1b7 The Origins of the Universe

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AQA GCSE Physics 1b-7The Origins of the Universe

• GCSE Physics pages 106 to 115

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AQA GCSE Specification

• THE UNIVERSE
• 11.7 What do we know about the origins of the
  Universe and how it continues to change?
• Using skills, knowledge and understanding of how
  science works
• to compare and contrast the particular
  advantages and disadvantages of using different
  types of telescope on Earth and in space to make
  observations on and deductions about the
  universe.
• Skills, knowledge and understanding of how
  science works set in the context of
• If a wave source is moving relative to an
  observer there will be a change in the observed
  wavelength and frequency.
• There is a red-shift in light observed from
  most distant galaxies. The further away galaxies
  are the bigger the red-shift.
• How the observed red-shift provides evidence
  that the universe is expanding and supports the
  big bang theory (that the universe began from a
  very small initial point).
• Observations of the solar system and the
  galaxies in the universe can be carried out on
  the Earth or from space.
• Observations are made with telescopes that may
  detect visible light or other electromagnetic
  radiations such as radio waves or X-rays.

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The expanding UniverseNotes questions from pages
106 107

• (a) What is a galaxy? (b) What is the name of our
  galaxy?
• (a) What is a light year? (b) How big is our
  galaxy?
• Copy and answer question (a) on page 106.
• (a) What is red shift (b) What causes red
  shift? (c) What is blue shift (d) What causes
  blue shift?
• Explain how the Doppler effect occurs with sound
  waves.
• (a) What did Edwin Hubble discover about distant
  galaxies? (b) Explain how his discovery led on to
  the idea of an expanding Universe.
• Copy and answer questions (b) and (c) on page
  107.
• Copy the Key Points on page 107.
• Answer the summary questions on page 107.

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The expanding Universe ANSWERS

• In text questions
• Because they are so far away.
• It is blue-shifted because its wavelength is
  reduced.
• Galaxy Y

• Summary questions
• (a) Orbiting
• (b) Expanding
• (c) Receding
• (d) Approaching
• 2. (a) Earth, Sun, Andromeda galaxy, Universe.
• (b) (i) Planet, star. (ii) Red-shift, galaxy

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The Big Bang Notes questions from pages 108 109

• What is the Big Bang theory of the origin of
  the Universe?
• What was the Steady State theory?
• (a) What is background microwave radiation? (b)
  Why does this radiation give support to the Big
  Bang theory?
• (a) Copy Figure 3 on page 109 and outline the
  various possible futures of the Universe. (b)
  What determines which future will occur?
• Copy and answer questions (a), (b) and (c) on
  pages 108 and 109.
• Copy the Key Points on page 109.
• Answer the summary questions on page 109.

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The Big Bang ANSWERS

• In text questions
• Nothing.
• It will be stretched even more to longer
  wavelengths.
• The exapnsion might reverse or it might just
  gradually stop.

• Summary questions
• (a) Created
• (b) Expanded
• (c) Detected
• (d) Stretched
• 2. (a) The Universe will continue to expand.
• (b) The expansion will stop and reverse.

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Looking into space Notes questions from pages
110 111

• In what ways do telescopes allow us to see more
  in the night sky?
• (a) What advantages do space telescopes have over
  ground based ones? (b) What are their
  disadvantages?
• (a) What are radio telescopes used for? (b) Why
  should their dishes be as large as possible?
• What are satellite detectors used for?
• Copy and answer questions (a), (b), (c) and (d)
  on pages 110 and 111.
• Copy the Key Points on page 111.
• Answer the summary questions on page 111.

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Looking into space ANSWERS

• In text questions
• A shooting star.
• The telescope collects more light from a star
  than the unaided eye does. So stars too faint to
  be seen with the unaided eye can be seen with a
  telescope.
• HST is in space above the atmosphere.
• The infra-red radiation is absorbed by the
  molecules of the gases in the atmosphere.

• Summary questions
• (a) Light, radio waves.
• (b) Gamma rays, infra-red radiation.
• 2. (a) Light from objects in space has to pass
  through the Earths atmosphere to reach
  ground-based telescopes. The Earths atmosphere
  scatters the light slightly and smudges the
  images out. HST is above the Earths atmosphere,
  so its images arent affected.
• (b) Gamma rays cant pass through the
  atmosphere, so the detectors need to be above the
  atmosphere whereas radio waves can pass through
  the atmosphere.
• (c) (i) Massive exploding stars.
• (ii) Planets beyond the solar system.

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Looking into the unknown Notes questions from
pages 112 113

• No questions.

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How Science Works ANSWERS

• Hypothesis the Universe is much older than
  present evidence suggests.
• Theory the Big Bang theory for the creation of
  the Universe.
• Prediction the distance of the galaxies must be
  greater than calculated.
• Political influence Soviet Union after Stalin,
  inflenced the thinking of scientists.
• Importance of technology the building of a new,
  much larger, more powerful and more accurate
  telescope.