P8.2 Powering EarthExam-style questions

Name ..................................................................... Class .................. Date .....................

1 The chart shows the methods used to generate electricity in the UK in 2013.

a Calculate the percentage of electricity that was generated from ‘other fuels’.Show your working.

Percentage: % (2 marks)

b i Describe what is meant by a renewable energy source.

(1 mark)

ii Name two examples of a renewable energy source.

1

2 (2 marks)

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P8.2 Powering EarthExam-style questions

Name ..................................................................... Class .................. Date .....................

c A wind farm is used to power machinery and lights in a factory in a remote hilly area.

Give one advantage and one disadvantage of using solar panels as a back-up energy resource.

Advantage:

Disadvantage:

(3 marks)

2 The traces from an oscilloscope show two input voltages.

a Which trace shows an alternating voltage?

(1 mark)

b Name an example of a source of alternating current.

(1 mark)

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P8.2 Powering EarthExam-style questions

Name ..................................................................... Class .................. Date .....................

3 The graph shows how the world’s energy source use has changed between 1820 and 2010.

a Describe the trend in the graph, and suggest two reasons for the changes over time.

(3 marks)

b Climate scientists are monitoring the world’s energy use.Why would a graph like this one be useful to them?

(2 marks)

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P8.2 Powering EarthExam-style questions

Name ..................................................................... Class .................. Date .....................

4 The National Grid ensures that electricity is supplied to all parts of the country.a Suggest two factors the government considers when building a new power

station to supply the National Grid.

1

2 (2 marks)

b Explain how transformers are used in the National Grid, and why they help to improve efficiency when transferring energy.

(6 marks)

c A transformer has an input voltage of 230 V and an output voltage of 1.5 V.Determine the current in the secondary coil if the current in the primary coil is 1 mA.Give your answer to 2 significant figures. Use the equation:

potential difference across primary coil × current in primary coil = potential difference

across secondary coil × current in secondary coil

Current: A (5 marks)

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P8.2 Powering EarthExam-style questions

Name ..................................................................... Class .................. Date .....................

5 The diagram shows a plug for mains supply in the UK.

a What is the potential difference between the live wire and the neutral wire?A 0 VB 15 VC 230 VD 240 V

Your answer (1 mark)

b Describe the role of the fuse.

(3 marks)

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