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• Fossil fuels are a finite resource, meaning that they cannot be replaced once extracted from the ground
• In 2015, 80 per cent of energy consumed in the world came from fossil fuels
• In early 2018, the UK's dependence on fossil fuels was at a low of 77 per cent
• Examples of fossil fuels

  • coal
  • natural gas
  • oil
• Coal used for electricity generation

  1. Burning of coal, usually crushed first

  2. Heating water to form steam

  3. Steam builds up pressure and spins a turbine

  4. Turbine connected to an electrical generator
• Coal


  • Enough coal on Earth to last hundreds of years
  • Produces high amounts of energy
• Coal


  • Produces carbon dioxide when burned, contributing to global warming
  • Damage is caused to natural land when mining takes place
• Natural gas


  • Emits less carbon dioxide than coal or oil
  • The UK has shale gas deposits
• Natural gas


  • Gas is highly flammable - if there is a gas leak, an explosion can easily happen
  • Extracting gas might cause the pollution of water
• Oil


  • A small amount of oil can produce a lot of energy
  • It is relatively easy to store and transport
• Oil


  • Creates significant air pollution when burned
  • Considerable impact on water, land use and disposal
• Modern material


  A material that has been developed through the invention of new or improved processes to improve the properties of the material, eg to make them stronger, faster, lighter and tougher
• Modern materials


  • Concrete
  • Aluminium
  • Steel
• Graphene


  • A single carbon layer material which is hypothetically 100 times stronger than steel
  • Could provide body armour that is bulletproof, invisible and almost weightless
  • If the whole of Wembley Stadium was covered in a layer of graphene, it would be almost invisible and be unbreakable, yet it could all be lifted it with one finger
• Liquid crystal displays (LCDs)


  Use the light-modulating properties of liquid crystals to display an image
• Liquid crystals


  • Are between a liquid and solid state
  • When charge is applied, the shape changes to either block light or let light through
• Organic light-emitting diodes (OLEDs)

  • Allow devices to be thinner and lighter than LCDs
  • More expensive as each pixel is its own light
  • Allow for thinner panels and better colour and contrast
• Nanomaterials


  Tiny particles of 1 to 100 nanometres (nm) that can be used in thin films or coatings
• Nanomaterial applications


  • Oleophobic coatings on smartphone screens that repel greasy fingerprints
  • Hydrophobic materials that repel water
• Breathable fabrics


  Allow body moisture to evaporate away from the body, through the use of a breathable membrane laminated between layers of fabric, whilst still remaining waterproof
• Breathable fabric examples


  • Gore-Tex
  • Permatex
  • SympaTex
• The systems approach to designing with programmable electronic devices is vital in understanding how today's electronic devices are programmed together with how they operate in the real world
• Systems


  The series of events that makes a system
• System block diagram


  • Considers the 'input, process and output' of a system
  • How the system will work is the 'process'
  • The 'input' is the part of the system that enables the process to start happening
  • They work together by sending signals to each other to make something happen
  • There can be more than one element in each section: input - starts the process, process - the thought process in the middle, output - the response or outcome
• Example system diagram


  • Vending machine
• Block diagrams


  • Clear, simple diagrams showing all of the input, process and output elements that make up the system being designed
  • They are easy to read and show how the circuit will work
• Example block diagram


  • Radiator
• Flowcharts


  • Clear diagrams showing the individual steps that will take place in the process
  • The shapes of the boxes always show a specific purpose
• Circuit diagrams


  • Use simplified universal symbols to represent the electronic circuit and its components
  • Show how the components are connected
  • Understood across the world so others can follow them and make the same circuit
  • A graphical representation of how the electronic circuit has been joined
• The systems approach to designing with programmable electronic devices is vital in understanding how today's electronic devices are programmed together with how they operate in the real world
• Systems


  The series of events that makes a system
• System block diagram


  • Considers the 'input, process and output' of a system
  • How the system will work is the 'process'
  • The 'input' is the part of the system that enables the process to start happening
  • They work together by sending signals to each other to make something happen
  • There can be more than one element in each section: input - starts the process, process - the thought process in the middle, output - the response or outcome
• Block diagrams


  • Clear, simple diagrams showing all of the input, process and output elements that make up the system being designed
  • They are easy to read and show how the circuit will work
• Flowcharts


  • Clear diagrams showing the individual steps that will take place in the process
  • The shapes of the boxes always show a specific purpose
• Circuit diagrams


  • Use simplified universal symbols to represent the electronic circuit and its components
  • Show how the components are connected
  • Understood across the world so others can follow them and make the same circuit
  • A graphical representation of how the electronic circuit has been joined
• Mechanical devices


  Can change one form of force to another
• Mechanical devices


  • All moving parts work on some sort of mechanism
• Motion


  The movement of a product
• Visible motion


  Motion that can be seen, e.g. scissors blades
• Hidden motion


  Motion that is not visible, e.g. sewing machine needle