P6.2 Global Challenges Part 2
Navigate to resources by choosing units within one of the unit groups shown below.
PM6.2i - apply: potential difference across primary coil (V) x current in primary coil (A) = potential difference across secondary coil (V) x current in secondary coil (A)
P6.2a – describe the main energy sources available for use on Earth, compare the ways in which they are used and distinguish between renewable and non-renewable sources
P6.2b - explain patterns and trends in the use of energy resources
P6.2c - recall that, in the national grid, electrical power is transferred at high voltages from power stations, and then transferred at lower voltages in each locality for domestic use
P6.2d - recall that step-up and step-down transformers are used to change the potential difference as power is transferred from power stations
P6.2e - explain how the national grid is an efficient way to transfer energy
P6.2f - recall that the domestic supply in the UK is a.c. at 50Hz and about 230 volts
P6.2g - explain the difference between direct and alternating voltage
P6.2h - recall the differences in function between the live, neutral and earth mains wires, and the potential differences between these wires
P6.2i - explain that a live wire may be dangerous even when a switch in a mains circuit is open, and explain the dangers of providing any connection between the live wire and earth
In topic P6.2 global challenges learners get to experience and look in depth at how electricity has transformed our lives. Learners get to look at the science that goes on behind the scenes when you switch on the kettle or your lights. This topic relates heavily to our daily lives and how we use electricity.
Learners look at the science of producing electrical energy from renewable and non-renewable sources (P6.2 a,b). More emphasis is placed on power stations and the method of transferring the electricity from power stations to houses using the national grid and transformers (P6.2 c,d,e,f,g). .
Learners should already be familiar with some concepts from Key Stage 3 such as calculations in a domestic context e.g. power used, cost of electricity and the units that are involved. They should already have looked at the basic concepts of electricity. At KS4 some of the concepts are revisited such as P3.2 simple circuits where leaners should have a good understanding of what electricity is.
- A common area of misunderstanding is the definition of a fossil fuel, it can lead to the labelling of nuclear power as a fossil fuel.
- Learners may think that all the electrons that make up the current are contained inside the generator that is the source of electricity.
- Learners may have difficulty understanding how a transformer works so it is best to make it as visual and practical as possible, modelling it is a good starting point.
- Learners may think main sockets have current inside them, which comes out as a plug goes in.
This task focuses on points P6.2 a,b. This task is split up in to 3 separate sub-tasks. It can be used as an assessment task after a lesson or as a method for testing learners’ Key Stage 3 knowledge. For task 1a learners are to read the text and underline statements that refer to renewable or non-renewable sources using two different colours. Task 1b learners place the different sources as either renewable or non- renewable energy source. Task 1c learners look at the advantages and disadvantages of each energy source.
Please see useful resource link on the right hand side:
- A video which shows how electricity can be made from renewable sources.
- An interactive internet research task that learners can use to guide them through researching how electricity is generated.
This task would work well as a starter or plenary activity and focuses of points P6.2 c,d,e. Learners arrange the keywords of the national grid into the correct order and then write 100 words explaining how it transports electricity over large distances. Please see useful resource link on the right hand side: a video which explains the national grid. Arrange the following into the correct order showing the national grid.
Correct order: Power station Step up transformer Pylons Step down transformer House
Extension Using the above order explain how the national grid transfers electricity from powers station to the home (no more than 100 words)
Learners answer will vary so long as they cover each keyword above correctly within 100 words
This task focuses on points P6.2 f,g. It can be done as a main to test learners’ understanding of transformers. This task focuses on the learners’ mathematical skills and their ability to complete calculations whilst applying the formula.
Please see useful links on resources on the right hand side:
- Good for general information about transformers.
- Video explaining how transformers work.
- Animation showing how transformers work.
OCR’s resources are provided to support the teaching of OCR specifications, but in no way constitute an endorsed teaching method that is required by the Board and the decision to use them lies with the individual teacher. Whilst every effort is made to ensure the accuracy of the content, OCR cannot be held responsible for any errors or omissions within these resources. We update our resources on a regular basis, so please check the OCR website to ensure you have the most up to date version.
© OCR 2017 - This resource may be freely copied and distributed, as long as the OCR logo and this message remain intact and OCR is acknowledged as the originator of this work.