ELC Component 5 – Energy transfer and efficiency Scheme of Work Summary of the Specification Content: By the end of this component, students should know: How energy is transferred by heating. What affects the rate of transfer of energy by heating. What is meant by the efficient use of energy. How we can insulate our homes. OUTCOME 1 Learning objective Learning Outcomes All bodies emit and absorb infra red radiation. The hotter an object is the more infrared energy it radiates in a given time. Know that thermal (heat) radiation is called infra red radiation. Explain that the hotter an object is the faster it will lose energy to the surroundings Possible Teaching & Learning Activities Starter, Main, Plenary Starter: How can you tell the difference between a hot and cold cup of water without touching it? Main: Use heat sensitive paper or thermochromic sheet to identify objects with greatest infrared energy. Use photochromatic lens (e.g. sunglasses) to track changes in infrared radiation during the day. Check observations using a thermometer. Resources & ICT Heat sensitive paper Thermochromic sheets Photochromatic lens (e.g. sunglasses) Thermometer Health & Safety Do not look directly at the sun Be aware of the risks of burning when using hot water Plenary: Complete worksheet and investigation, ‘Which object radiates the greatest infrared radiation?’ Version 1.0 1 Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX ELC Component 5 – Energy transfer and efficiency Scheme of Work OUTCOME 2 Learning objective Learning Outcomes Dark, matt surfaces are good absorbers and good emitters of infra red radiation. Light, shiny surfaces are poor absorbers and poor emitters of infra red radiation. Light, shiny surfaces are good reflectors of infra red radiation. Understand the meaning of the terms ‘absorb’ and ‘emit’. Describe how the nature of the surface determines how good and absorber or emitter it is. Realise that whether an object emits or absorbs infra red radiation depends on whether it is hotter or colder than its surroundings. Understand that infra red radiation can be reflected in the same way as light radiation. Version 1.0 Possible Teaching & Learning Activities Starter, Main, Plenary Starter: Why do people in some hot countries paint their houses white? Main: Explain the difference between absorption and emission Illustrate with some examples. Demonstrate infrared radiation being reflected in a concave mirror. Resources & ICT Health & Safety A good website to start with is http://www.gcsescie nce.com/pen10matt-black.htm Plenary: What would be the best colour to paint the radiators in your home – and why aren’t they painted this colour? 2 Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX ELC Component 5 – Energy transfer and efficiency Scheme of Work OUTCOME 3 Learning objective Learning Outcomes The use of kinetic theory to explain the different states of matter. The particles of solids, liquids and gases have different amounts of energy. Explain the differences between solids, liquids and gases in terms of the arrangement of particles Describe how by adding or removing energy, materials can be made to change their state. Version 1.0 Possible Teaching & Learning Activities Starter, Main, Plenary Resources & ICT Starter: Why does friction burn? (More energy applied = greater the temperature; e.g. rubbing your hands together) http://esfscience.wo rdpress.com/2009/0 9/27/kinetic-theorysummary-for-y9/ Health & Safety . Main: States of matter (water). Use the kinetic theory model to explain the different states of matter of water. Plenary: Issue worksheet with drawings of particles in solids liquids and gases. Students to label each one. 3 Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX ELC Component 5 – Energy transfer and efficiency Scheme of Work OUTCOME 4 Learning objective Learning Outcomes Possible Teaching & Learning Activities Starter, Main, Plenary The transfer of energy by conduction, convection, evaporation and condensation involves particles. Be able to identify which method of energy transfer (conduction, radiation, convection, evaporation or condensation is involved in a given situation. Know that of all these processes, only radiation does not involve particles of matter. Know that convection can only occur in liquids or gases. Starter: Why do saucepans have wooden handles? How do some birds stay in the air without flapping their wings? How is the grass wet (dew) on a sunny morning? Version 1.0 Main: Energy transfer using examples of conduction, convection and condensation. Conduction: metal spoon v wooden spoon in hot water Convection: tissue paper rises over hot radiator Condensation: ice cold container in a warm room collects condensation on its surface Resources & ICT Health & Safety A good interactive web site is http://www.wisconline.com/Objects/ViewObj ect.aspx?ID=SCE304 and this BBC site contains a video sequence http://www.bbc.co.uk/learnin gzone/clips/conductionconvection-andradiation/10589.html Plenary: 4 Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX ELC Component 5 – Energy transfer and efficiency Scheme of Work OUTCOME 5 Learning objective The factors that affect the rate of evaporation and condensation. Version 1.0 Possible Teaching & Learning Activities Starter, Main, Plenary Learning Outcomes Identify variables that affect the rate of evaporation and condensation, i.e. - temperature - wind - surface area Starter: How does evaporation help cool you down? Main: Factors which change the rate of evaporation and condensation (e.g. difference between liquid and air temperature; surface area/volume; type of material Plenary: How would you get washing to dry as fast as possible? 5 Resources & ICT Health & Safety There is a nice little YouTube video on http://www.youtube.com/wat ch?v=yyxc-81JDbo and a worksheet at this site http://www.primaryresource s.co.uk/science/pdfs/RDeva p.pdf Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX ELC Component 5 – Energy transfer and efficiency Scheme of Work OUTCOME 6 Learning objective Learning Outcomes The rate at which an object transfers energy by heating depends on: • surface area • the material from which the object is made • the nature of the surface with which the object is in contact. Recall factors that affect the rate at which an object transfers energy by heating. Version 1.0 Possible Teaching & Learning Activities Starter, Main, Plenary Starter: Show students a heat sink from a transistor or microchip and ask why it is designed in that way. Main: Discuss the design of the fins. Use other examples, e.g. car radiators and motor bike engines. Resources & ICT Health & Safety A website that teachers might find useful is http://www.physicsclassroo m.com/class/thermalP/u18l1 f.cfm Plenary: How does a heat-proof mat under a Bunsen burner reduce the rate at which thermal energy is transferred to the bench? 6 Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX ELC Component 5 – Energy transfer and efficiency Scheme of Work OUTCOME 7 Learning objective Learning Outcomes The bigger the temperature difference between an object and its surroundings, the faster the rate at which energy is transferred by heating. State that the hotter an object is, the faster it will transfer thermal energy to the surroundings. Version 1.0 Possible Teaching & Learning Activities Starter, Main, Plenary Resources & ICT Health & Safety Starter: What happens to the temperature of a hot cup of tea on a hot, mild and cold day? Main: Discus whether the temperature of the surroundings affects how quickly a liquid cools down. Plenary: Issue a work sheet showing objects at different temperatures in surroundings of different temperatures. Which will transfer energy the fastest? 7 Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX ELC Component 5 – Energy transfer and efficiency Scheme of Work OUTCOME 8 Learning objective Learning Outcomes Heating and insulating buildings. U-values measure how effective a material is as an insulator. The lower the U-value, the better the material is as an insulator. Identify different ways of insulating buildings, e.g.: - fibre glass insulation for roofs - foam insulation for cavity walls - carpet and underlay for floors - draught excluders for gaps Recall that the lower the U-value of a material, the better it is at insulating. Version 1.0 Possible Teaching & Learning Activities Starter, Main, Plenary Starter: Ask “How many ways can you think of that heat (thermal energy) can be lost from your home?” Main: Issue a diagram of a house showing the different ways in which energy can be lost. Discuss the different ways of reducing each loss. Remember that turning down the thermostat is just as effective as spending money on insulation in some cases. Explain the idea of U-values. Resources & ICT Health & Safety A useful website is http://www.energysavingtr ust.org.uk/Homeimprovements-andproducts/Homeinsulation-glazing Plenary: If you have very little money to spend on home insulation, which sort would you fit first and why? 8 Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX ELC Component 5 – Energy transfer and efficiency Scheme of Work OUTCOME 9 Learning objective Learning Outcomes When energy is transferred, only part of it may be usefully transferred, the rest is wasted. Wasted energy is eventually transferred to the surroundings, which become warmer. The wasted energy becomes increasingly spread out and so becomes less useful. Understand that not all of the input energy in a situation is transferred into the intended place or becomes the intended type of energy. Explain that wasted energy often goes into warming up the surroundings. Realise that as the energy becomes more spread out in the surroundings it becomes more difficult to use and so less useful Version 1.0 Possible Teaching & Learning Activities Starter, Main, Plenary Resources & ICT Health & Safety Starter: Name the ‘useful’ and ‘wasted’ energy in a list of ‘energy transfers’ A website that gives one perspective on energy Main: Discuss different types of energy and wastage is energy transfers. http://wwf.panda.org/about Look at energy saving labels from domestic _our_earth/aboutcc/cause/ appliances, e.g. fridges. Why do some use wasting_energy_eff/ more energy than others? Plenary: Why is it important that energy is not wasted? 9 Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX ELC Component 5 – Energy transfer and efficiency Scheme of Work OUTCOME 10 Learning objective Learning Outcomes The greater the percentage of the energy that is usefully transformed in a device, the more efficient the device is, eg the comparison between filament lamps and fluorescent tubes. Explain that efficient devices are those that change more of the input energy into the intended, useful form of energy. Version 1.0 Possible Teaching & Learning Activities Starter, Main, Plenary Starter: How do electrical appliances waste energy? Main: Evaluate the efficiency of different electrical appliances e.g. filament lamps and fluorescent tubes Plenary: Is it possible for a device to be more than 100% efficient? 10 Resources & ICT Health & Safety A good website for energy efficiency is http://www.npower.com/Home/ Energy-efficiency/Savingenergy/Efficientproducts/index.htm Copyright © 2011 AQA and its licensors. All rights reserved The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723). Registered address: AQA, Devas Street, Manchester M15 6EX