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  • Created by: tegan.xx0
  • Created on: 03-03-15 09:59
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    • Photo Cells
      • Produces DC current
      • Can Operate in remote locations.
      • Transfers light energy into electricity
      • The amount of power you make depends on the surface area of light.
      • How photos cells work:
        • 1. Energy is absorbed by silicon atoms(light)
        • 2. Electrons- knocked off silicon atoms
        • 3. Electrons can flow
    • Solar Cell
      • Uses the suns thermal energy to heat water
    • Wind Turbines
      • Mirrors reflect the light
      • Advantages
        • Renewable energy resource
        • Don't produce waste
      • Disadvantages
        • Spoils the landscape
    • Dynamo Effect
      • Ways to increase the dynamo effect
        • 1. Increase the size of the magnet
        • Increase the number of coils
        • Increase the speed you move the magnet
      • Efficiency= useful energy output (x100) / total energy output
        • Efficiency will not be over 100%
    • Greenhouse Effect
      • 1. Electromagnetic radiation from the sun enters the earths atmosphere.
      • 2. but when they travel out into space, some radiations are to weak to escape.
      • 3. so they are kept in the earths atmosphere. These then keep warming up the sun.
      • 4. The earths atmosphere gets thicker because of dust and other man mad sources.
      • Natural Green house gases:
        • Decomposing plant material.
        • Evaporations from oceans lakes and rivers.
        • Respiration by plants and animals, forest fires and volcanoes.
      • Man Made Greenhouse Gases:
        • Rice paddy fields, cattle and coal mines.
        • Burning hydrocarbon fuels.
        • Making cement, burning fuels.
    • Chosing the right fuel:
      • Toxicity
      • Energy Value
      • Availability
      • Cost
      • Useability
      • Pollution
      • Storage
    • Ionising Radiation
      • Alpha
        • Least Penetrating, can be stopped by a piece of paper.
        • Used in smoke detectors.
        • Very dangerous, easily absorbed by cells.
      • Gammma
        • Most penetrating, can be stopped by lead.
        • Used to sterilise surgical instruments, kills harmful bacteria in food.
        • Not as dangerous, less likely to be absorbed by a cell.
        • Kills cancer cells.
      • Beta
        • Is slightly more penetrating than Alpha. Stopped by a thin sheet of Aluminium
        • Used for tracing and monitoring the thickness of materials.
        • less likely to be absorbed by a cell

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