AQA GCSE Physics 1a4 Generating Electricity

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AQA GCSE Physics 1a-4Generating Electricity

• GCSE Physics pages 62 to 73

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AQA GCSE Specification

• ENERGY RESOURCES THE GENERATION OF ELECTRICITY
• 11.4 How should we generate the electricity we
  need?
• Using skills, knowledge and understanding of how
  science works
• to compare and contrast the particular
  advantages and disadvantages of using different
  energy sources to generate electricity.
• Skills, knowledge and understanding of how
  science works set in the context of
• In most power stations an energy source is
  used to heat water. The steam produced drives a
  turbine which is coupled to an electrical
  generator.
• Common energy sources include coal, oil and
  gas, which are burned to produce heat and
  uranium/plutonium, in which nuclear fission
  produces heat.
• Energy from renewable energy sources can be
  used to drive turbines directly.
• Renewable energy sources used in this way
  include wind, the rise and fall of water due to
  waves and tides, and the falling of water in
  hydroelectric schemes.
• Electricity can be produced directly from the
  Suns radiation using solar cells.
• In some volcanic areas hot water and steam
  rise to the surface. The steam can be tapped and
  used to drive turbines. This is known as
  geothermal energy.
• Using different energy resources has different
  effects on the environment. These effects include
  the release of substances into the atmosphere,
  noise and visual pollution, and the destruction
  of wildlife habitats.
• The advantages and disadvantages of using
  fossil fuels, nuclear fuels and renewable energy
  sources to generate electricity. These include
  the cost of building power stations, the start-up
  time of power stations, the reliability of the
  energy source, the relative cost of energy
  generated and the location in which the energy is
  needed.

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Fuel for electricityNotes questions from pages
62 63

• Copy figure 1 on page 62.
• Explain the differences between coal and gas
  fired power stations.
• Copy and answer questions (a) and (b) on page 62.
• Copy figure 4 on page 63.
• What is nuclear fission?
• Explain how a nuclear power station produces
  electricity.
• Copy the table on page 63.
• Copy the Key Points on page 63.
• Answer the summary questions on page 63.

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Fuel for electricityANSWERS

• In text questions
• It goes into the cooling tower, where it
  condenses into water.
• It is carried away by the hot water from the
  cooling tower escaping into the air.

• Summary questions
• 1. (a) uranium (b) gas (c) oil, uranium
• 2. (a) (i) Advantage of oil-fired station no
  radioactive waste disadvantage produces
  greenhouse gases.
• (ii) Advantage of gas-fired station can be
  started quicker disadvantage gas supplies will
  run out before coal supplies.
• (b) 10 000 kg
• (c) Balanced arguments for and against required.

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Energy from wind and waterNotes questions from
pages 64 65

• Describe a wind turbine.
• Copy and answer question (a) on page 64.
• Copy figure 2 on page 64 and describe how waves
  can generate electricity.
• Copy and answer question (b) on page 64.
• What is (a) hydroelectric power and (b) tidal
  power?
• Copy and answer questions (c) and (d) on page 65.
• Copy the Key Points on page 65.
• Answer the summary questions on page 65.

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Energy from wind and water ANSWERS

• In text questions
• No electricity is generated
• Too much electricity would be needed to pump the
  water uphill.
• From the gravitational potential energy of water
  in the reservoirs.
• The tides are very predictable whereas the wind
  isnt.

• Summary questions
• (a) wind
• (b) tidal
• (c) hydroelectric
• (d) wave
• 2. (a) (i) 1000 (ii) 25 km
• (b) From top to bottom hilly or coastal
  areas, estuaries, coastline, mountain areas.
• (c) Check reasons given.

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Power from the Sun and the EarthNotes questions
from pages 66 67

• What is solar power?
• Describe how (a) solar cells and (b) solar
  heating panels make use of solar power.
• Copy and answer questions (a) and (b) on page 66.
• What is geothermal energy?
• Explain how geothermal energy can be used to
  generate electricity.
• Copy and answer question (c) on page 67.
• Copy the Key Points on page 67.
• Answer the summary questions on page 67.

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Power from the Sun and the Earth ANSWERS

• In text questions
• Solar cell
• The motor stops
• The energy is from radioactive substances inside
  the Earth.

• Summary questions
• (a) solar energy
• (b) radioactivity, geothermal energy
• (c) radiation
• 2. (a) 1500
• (b) To supply electricity when the solar
  panels are in darkness
• Advantages of solar energy widely available,
  simple set up domestic use possible.
• Disadvantages Not continuously available (eg
  not at night!), smaller scale electricity
  generation

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Energy and the enviromentNotes questions from
pages 68 69

• Copy the pie chart on page 68.
• What are the problems of using fossil fuels?
• Copy and answer question (a) on page 68.
• Why are fossil fuels used?
• List the advantages and disadvantages of nuclear
  power compared with renewable sources.
• Copy and answer question (b) on page 69.
• List the advantages and disadvantages of using
  renewable energy sources.
• Copy and answer question (c) on page 69.
• Copy the Key Points on page 69.
• Answer summary questions 1 and 2 on page 69.

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Energy and the enviroment ANSWERS

• In text questions
• (i) carbon dioxide (ii) sulfur dioxide
• It turns into radioactive waste when it is used.
• They affect birds and can upset humans.

• Summary questions
• (a) fossil fuels
• (b) acid rain, greenhouse gas.
• (c) radioactive waste, plant and animal
  life.
• (i) A (ii) D
• (iii) C (iv) B

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Big energy issues Notes questions from pages 70
71

• Answer questions 1 and 2 on pages 70 and 71.

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Big energy issues ANSWERS

• (a) Not enough electricity would be generated at
  night if there were no wind or waves.
• (b) More pumped storage schemes would be
  needed to store electricity when it is not
  needed.
• 2. Fusion relies on fusing together heavy
  hydrogen (deuterium) atoms. There is an almost
  unlimited supply of this in seawater and so we
  could produce electricity for thousands of years.

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How Science Works ANSWERS

• Tamara could have used a piece of card and placed
  it over different parts of the solar cell. All
  other variables would have been kept the same.
  Each time she would record the voltage. Each time
  the voltage would remain the same.
• Results show that covering more of the solar cell
  reduces the voltage.
• Tamaras independent variable was an ordered
  variable and so was not as powerful as a
  continuous variable.
• To improve her independent variable, Tamara
  should have measured the area of the solar cell
  covered, this would have been a continuous
  variable. This would have allowed Tamara to
  produce a graph and her conclusion would have
  been more powerful.

• The readings were only to 0.1 volts and this did
  not produce a difference between some of the
  readings for different exposures. The voltmeter
  was not sensitive enough.
• Farzana probably suggested a digital voltmeter
  that read to 0.01 volts.
• Yes, even when the solar cell is completely
  covered there is a reading of 0.1 volts.
• She could start again! Realistically she should
  take 0.1 volts off each of the readings.