National & global energy resources

Fossil fuels are burned in car engines and in power stations.

Describe how different energy stores change in a car engine when a fossil fuel is burned.

Some car engines burn a fuel that is produced using plants.

Name a fuel produced using plants.

Some cars do not contain an engine that burns a fuel.

Suggest how cars that do not burn a fuel are powered.

Figure 6 shows how the total amount of electricity generated in the UK has changed with time.

The proportion of electricity that is generated using renewable energy resources has increased since the year 2013.

Which conclusion is correct?

Use Figure 6.

Tick () one box.

The UK plans to stop burning fossil fuels to generate electricity.

Explain one reason why it will take many years before all electricity is generated using renewable resources.

Renewable energy resources can have a negative impact on the environment.

Give one negative environmental impact of hydro-electric power and of wind power.

Hydro-electric power

Fossil fuels are burned in car engines and in power stations.

Describe how different energy stores change in a car engine when a fossil fuel is burned.

Some car engines burn a fuel that is produced using plants.

Name a fuel produced using plants.

Some cars do not contain an engine that burns a fuel.

Suggest how cars that do not burn a fuel are powered.

Figure 1 shows how the total amount of electricity generated in the UK has changed with time.

The proportion of electricity that is generated using renewable energy resources has increased since the year 2013.

Which conclusion is correct?

Use Figure 1.

Tick () one box.

The UK plans to stop burning fossil fuels to generate electricity.

Explain one reason why it will take many years before all electricity is generated using renewable resources.

Renewable energy resources can have a negative impact on the environment.

Give one negative environmental impact of hydro-electric power and of wind power.

Hydro-electric power

Figure 2 shows an outdoor swimming pool.

The water in the swimming pool comes from the sea.

The water in the pool is heated using a geothermal energy resource.

Which of the following describes a geothermal energy resource?

Tick (✓) one box.

15 kg of seawater is heated before it is added to the pool.

specific heat capacity of seawater = 3800 J/kg °C

Calculate the change in thermal energy of 15 kg of seawater when its temperature is increased by 9.0 °C.

Use the equation:

change in thermal energy = mass × specific heat capacity × temperature change

The energy transferred from 1.0 m² of the surface of the pool to the air is 80 J each second.

The surface area of the pool is 120 m².

Calculate the energy transferred from the whole surface of the pool to the air each second.

Which of the following units is the same as 1 J/s?

Tick (✓) one box.

The pool is above sea level.

5.0 kg of water is pumped from sea level into the pool.

The water gains 196 J of gravitational potential energy.

gravitational field strength = 9.8 N/kg

Calculate the height of the pool above sea level.

Use the equation:

The water in some swimming pools is heated by burning fossil fuels.

Explain one environmental disadvantage of burning fossil fuels.

Wind power and solar power are both renewable energy resources used to generate electricity for the National Grid.

Which of the following is also a renewable energy resource?

Tick (✓) one box.

The energy transferred by the National Grid in one second was 36 gigajoules (GJ).

Which of the following is the same as 36 gigajoules?

Tick (✓) one box.

Figure 6 shows how the mean power output from solar and wind energy resources in the UK varied between 2014 and 2019.

Figure 7 shows how the power output from solar and wind energy resources varies in a typical year.

Explain the changes in power output from solar and wind energy resources between

2014 and 2019.

You should include an explanation of the change in power output during a typical year.

Wind power and solar power are both renewable energy resources used to generate electricity for the National Grid.

Which of the following is also a renewable energy resource? Tick (✓) one box.

The energy transferred by the National Grid in one second was 36 gigajoules (GJ). Which of the following is the same as 36 gigajoules? Tick (✓) one box.

Figure 1 shows how the mean power output from solar and wind energy resources in the UK varied between 2014 and 2019.

Figure 2 shows how the power output from solar and wind energy resources varies in a typical year.

Explain the changes in power output from solar and wind energy resources between

2014 and 2019. You should include an explanation of the change in power output during a typical year.

Figure 9 shows some of the energy resources used to meet the demand for electrical power in the UK on one day in 2020.

The maximum demand for electrical power on that day was at 6 pm.

Determine the percentage of the maximum demand for electrical power that was generated using gas.

The UK government wants to reduce carbon emissions as much as possible.

Which energy resources need to be used less to achieve this?

Tick (✓) one box.

A network of transformers and transmission cables transfers electrical power from

power stations to consumers.

What is this network called?

Explain how using step-up transformers makes the network efficient.

Figure 1 shows some of the energy resources used to meet the demand for electrical power in the UK on one day in 2020.

The maximum demand for electrical power on that day was at 6 pm. Determine the percentage of the maximum demand for electrical power that was generated using gas.

The UK government wants to reduce carbon emissions as much as possible. Which energy resources need to be used less to achieve this? Tick (✓) one box.

A network of transformers and transmission cables transfers electrical power from power stations to consumers.

What is this network called?

Explain how using step-up transformers makes the network efficient.

Solar intensity is a measure of the radiation received from the Sun at the surface of the Earth.

Figure 7 shows how the mean solar intensity changes with the distance from the equator.

The city of Athens is 4200 km from the equator.

What is the mean solar intensity in Athens?

Solar water heaters use radiation from the Sun to heat water.

The heated water is stored in a water tank.

Figure 8 shows a solar water heater on the roof of a building.

Cities closer to the equator have many more buildings with solar water heaters than cities further away from the equator.

Suggest why.

The use of solar water heaters may reduce the need to burn fossil fuels.

Complete the sentence.

Choose the answer from the box.

Burning fossil fuels contributes to global warming because there is an increase in

The efficiency of the solar water heater is 0.61

Calculate the useful power output when the total power input to the solar water heater is 1100 W.

Use the equation:

useful power output = efficiency × total power input

Different solar water heaters have different sized heating panels.

Suggest how the size of the heating panels affects the input power to a solar water heater.

Water has a high specific heat capacity.

What is meant by the specific heat capacity of water?

Tick (✓) one box.

The water tank contained 80 kg of water.

The change in thermal energy of the water was 8 400 000 J.

specific heat capacity of water = 4200 J/kg °C

Calculate the temperature change of the water.

Use the Physics Equations Sheet.

The water tank is thermally insulated.

How does thermal insulation affect the rate of energy transfer from the water in the tank?

Tick (✓) one box.

Table 1 shows information about different materials.

Which material in Table 1 is the best thermal insulator?

Tick (✓) one box.

Figure 4 shows a sailing boat crossing an ocean.

There is a wind turbine on the boat.

The wind turbine generates electricity to charge a battery on the boat. Name one other renewable energy resource that could be used on the boat to generate electricity.

The boat also has a generator that burns a fossil fuel. The battery can be charged by either the wind turbine or the generator. Give two reasons why this is useful.

Explain one environmental impact of using fossil fuels to generate electricity.

The kinetic energy of the boat is 81 kJ. mass of boat = 8000 kg Calculate the speed of the boat.

As the boat passes over a wave, the gravitational potential energy of the boat increases by 19 600 J. mass of boat = 8000 kg gravitational field strength = 9.8 N/kg Calculate the change in height of the centre of mass of the boat as it passes over the wave.

An eco-house is designed to be environmentally friendly. Figure 4 shows a picture of an eco-house.

The solar panels and a wind turbine are used to generate electricity for the eco-house. Solar and wind are both renewable energy resources. What does renewable energy resource mean? Tick (✓) one box.

Biomass, nuclear and natural gas are three other energy resources. Complete the table to show whether each energy resource is renewable or non-renewable.

Moving air makes the wind turbine spin. The wind turbine generates electricity which is used to charge a battery. Complete the sentences. Choose answers from the box.

energy.

battery.

The roof of the eco-house is covered with soil. Covering the roof with soil decreases the thermal conductivity of the roof. What are the advantages of having a roof with a lower thermal conductivity? Tick (✓) two boxes.

The average power transferred to the solar panels by sunlight is 26 000 W Calculate the average energy transferred to the solar panels in 30 seconds. Use the equation: energy transferred = power × time

Write down the equation that links efficiency, total power input and useful power output.

The solar panels on the roof of the eco-house have an efficiency of 0.15 The average power input to the solar panels is 26 000 W Calculate the average useful power output from the solar panels.

Explain why it is a good idea for the eco-house to have both a wind turbine and solar panels.

Figure 5 shows a wood-fired hot tub.

What type of fuel is wood? Tick (✓) one box.

Give two environmental effects of using wood as an energy resource.

Describe the change to the stores of energy of the wood, pipe and water as the water is heated.

The temperature of the water reaches 42 °C The temperature then stays constant even though the fire continues to burn. Explain why the temperature of the water stays constant.

A student investigated how the area of a solar panel affected the output potential difference of the solar panel.

The student placed different sized solar panels under a lamp.

Figure 3 shows a solar panel under a lamp.

Which variable should be controlled?

Tick (✓) one box.

The student measured the output potential difference using a voltmeter.

When the voltmeter was not connected, the reading on the voltmeter was 0.7 V

What name is given to this type of error?

Tick (✓) one box.

Table 1 shows the results of the investigation.

The readings for which solar panel show an anomalous result?

Tick (✓) one box.

The student did not have a solar panel with an area of 40 cm²

Determine the most likely value for the mean output potential difference of a 40 cm² solar cell.

The total input energy transfer to one of the solar panels was 8.0 joules.

The useful output energy transfer was 0.96 joules.

Calculate the efficiency of the solar panel.

Use the equation:

Solar power is a renewable energy resource.

Complete the sentence.

Choose the answer from the box.

Some homes have solar panels which generate electricity.

On a sunny day the potential difference across a solar panel is 31 volts.

A charge of 490 coulombs flows through the solar panel.

Calculate the energy transferred by the solar panel.

Use the equation:

energy transferred = charge flow × potential difference

Give your answer to 2 significant figures.

Why do solar panels on homes help reduce the environmental impact of using electrical devices?

Tick (✓) one box.

A hybrid car has an electric motor and a petrol engine.

Petrol is a non-renewable energy resource. What is meant by a non-renewable energy resource?

The electric motor in the car is powered by a battery. To charge the battery, the car is plugged into the mains supply at 230 V The power used to charge the battery is 6.9 kW Calculate the current used to charge the battery.

Mains electricity is an ac supply. Explain the difference between direct and alternating potential difference.

The cable used to connect the car to the mains electricity supply has a low resistance. Explain why it is better to use a cable with a low resistance than to use a cable with a high resistance.

There are many different energy resources.

Which two energy resources are renewable?

Tick two boxes.

Some non-renewable energy resources are more reliable than others.

Which statement correctly describes a reliable resource?

Tick one box.

Figure 1 shows a wind farm.

The total power output of the wind farm is 19.6 MW

All of the wind turbines have the same power output.

What is the power output of one wind turbine?

Tick one box.

Give two reasons why people might not like having wind turbines near their homes.

Figure 2 shows the electricity generated by different energy resources in the UK.

The total amount of electricity generated was the same in 2014 and in 2015

There are changes in the amounts of different energy resources used between 2014 and 2015

Explain the environmental impacts of the changes.