Exam-style Questions: Energy Transfers

  1. a) A wind powered generator is used to produce electrical power when the wind is blowing. The table shows the electrical power generated by the wind for different wind speeds.

    Power generated

    (watts)

    0 0 140 900 1100 1160 1160

    Wind Speed

    (km/h)

    0 2 5 10 12 15 20

    i) On the axes below draw a graph to show how the power generated changes with wind speed.

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    (3 Marks)

    ii) What is the lowest wind Speed needed to generate power?

    (1 Mark)

    iii) What is the maximum power generated by the wind?

    (1 Mark)

    iv) Explain one disadvantage of using only a wind generator as the source of electrical power

    (1 Mark)

    b) Complete the sentence to show the energy transfer taking place in the wind powered generator

    ........... Energy is transferred to ............energy.

    (2 Marks)

    (Marks available: 8)

    Answer

    Answer outline and marking scheme for question: 1

    a)

    i) points plotted correctly;

    smooth curve drawn

    (3 Marks)

    ii) about 3km/h

    (1 Mark)

    iii) 1160 watts

    (1 Mark)

    iv) not always windy/variable output/too much land needed

    (1 Mark)

    b) kinetic/movement; electrical

    (2 Marks)

    (Marks available: 8)

  2. The main heat energy losses from a house are shown in the diagram.

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    a) Complete the diagram to show the percentage heat energy loss through the walls.

    (1 Mark)

    b) Complete the table below to show how the heat energy loss from each part of the house can be reduced. The first one has been done for you.

    Part of the house Method used for reducing heat energy loss
    roof glass-fibre insulation in the loft
    walls ...............................................................
    floor ...............................................................

    (2 Marks)

    (Marks available: 3)

    Answer

    Answer outline and marking scheme for question: 2

    a) 65°

    (1 Mark)

    b) Walls: draught excluder/curtain/cavity walls insulation

    Floor: carpets/wooden floors

    (2 Marks)

    (Marks available: 3)

  3. a) name a renewable energy resource.

    (1 Mark)

    b) Describe three main advantages that renewable energy resources have over non-renewable resources for the generation of electricity.

    (3 Marks)

    c) You are a scientist who wants to use more renewable energy.

    Suggest how you would persuade people to want more renewable energy sources

    (4 Marks)

    (Marks available: 8)

    Answer

    Answer outline and marking scheme for question: 3

    a) Any of these: wind, wave, tidal, geothermal, solar , wood

    (1 Mark)

    b)

    Will not run out;

    No waste;

    No fuel cost;

    No transportation cost

    (3 Marks)

    c) present/communicate scientific evidence for use of:

    renewable energy sources (1)

    saves using other resources (1)

    limitless supply (1)

    no pollution / clean / environmental issues (1)

    or arguments based on use of non-renewable sources.

    (4 Marks)

    (Marks available: 8)

  4. This question is about keeping a house warm. A house has been insulated in these two ways.

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    Describe how each of these ways helps to keep the house warm. Use your ideas about conduction, convection and radiation.

    a) Double glazing.

    (2 Marks)

    b) Putting shiny aluminium foil on the wall behind a radiator.

    (2 Marks)

    (Marks available: 4)

    Answer

    Answer outline and marking scheme for question: 4

    a) trapped air

    (1 Mark)

    poor conductor/convector

    (1 Mark)

    b) reflects

    (1 Mark)

    radiation

    (1 Mark)

    (Marks available: 4)

  5. a) The devices shown below transfer electrical energy in different ways.

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    The list gives the useful form of energy the devices are deisgned to produce.

    Match words from the list with the devices numbered 1-4

    Heat (thermal energy)

    Light

    Movement (kinetic energy)

    Sound

    (4 Marks)

    b) Match words from the list with the numbers 1-4 in the sentences.

    Conduction

    Convection

    Insulation

    radiation

    Energy travels from the Sun the Earth by ............1...............

    In a kettle hot water rises by...............2.............

    Thermal energy passes through the walls of a room by ..............3...........

    To reduce heat loss from a house, the cavity walls are fitted with ...........4...............

    (4 Marks)

    (Marks available: 8)

    Answer

    Answer outline and marking scheme for question: 5

    a)

    • Light
    • Movement (kinetic energy)
    • Heat (thermal energy)
    • Sound

    (4 Marks)

    b)

    • Radiation
    • Convection
    • Insulation
    • Conduction

    (4 Marks)

    (Marks available: 8)

  6. a) The supply of energy from oil is decreasing. The supply from coal is increasing.

    Why is this a problem for the environment?

    (1 Mark)

    b) We have relied on fossil fuels to supply most of our energy needs. Why must we find alternative energy sources?

    (1 Mark)

    c) On average, the energy use of each family in the UK relases over 25 tonnes of carbon dioxide and 4 kilograms of sulphur diosxide into the air every year.

    i) State one environmental effect which is increased by releasing carbon dioxide into the atmosphere

    (1 Mark)

    ii) State a different environmental effect caused by releasing sulphur dioxide into the atmosphere

    (1 Mark)

    d) Electricity may be generated using nuclear fuels. Apart from the cost of the electricity, what are the advantages and disadvantages of doing this?

    (5 Marks)

    (Marks available: 9)

    Answer

    Answer outline and marking scheme for question: 6

    a) coal gives more CO2 than oil (for same energy)

    (1 Mark)

    b)

    the demand is rising (too rapidly)

    (1 Mark)

    resources insufficient to meet (future) demand

    (1 Mark)

    c)

    i) greenhouse (effect)

    (1 Mark)

    ii) (produces) acid rain

    (1 Mark)

    d) any five from: (there must be at least 2 advantages and 2 disadvantages for full marks)

    • no polluting gases released
    • large energy
    • so no increase in greenhouse effect/acid rain
    • when running normally very little radiation escapes
    • if an accident occurs (large) ammounts of radiation may be released
    • waste radioactive
    • waste has to be stored (safely) for a longtime/underground
    • take a long time to start up

    (5 Marks)

    (Marks available: 9)