This list provides a range of activities and demonstrations which will help students to develop an understanding of electric circuits. Included are practical tips, consideration of students' misconceptions and suggested teaching approaches.
The list covers the following statements in the 2014 curriculum:
• electric current, measured in amperes, in circuits, series and parallel circuits, currents add where branches meet and current as flow of charge
• potential difference, measured in volts, battery and bulb ratings; resistance, measured in ohms, as the ratio of potential difference (p.d.) to current
• differences in resistance between conducting and insulating components (quantitative)
Links and Resources
A common misconception about electric circuits is that the electricity comes out of the battery and travels very quickly to the bulb. The ‘Big circuit’ activity challenges this idea by comparing how quickly a bulb lights up in a small circuit and in a very big circuit (with several meters of wiring). Naturally, the students expect there to be a delay before the bulb lights in the big circuit due to the greater distance from the battery to the bulb. But the bulb lights immediately no matter how long the circuit is!
Ignore the fact that resource is called GCSE Teacher Activities. The Pupil Circuit activity described on page 4 is ideal for developing a model for electric circuits at Key Stage Three and for challenging the idea that current is used up by components in a circuit.
Ask one student to be a battery and give them a tub of balls. These represent the stored energy of a battery. Ask another student to be a light bulb, standing on the opposite side of the room with an empty tub. The rest of the students, the electrons, transfer the energy from the battery to the bulb, moving around the imaginary circuit in single file as if confined inside the wires, illustrating that the current is conserved.
The activity can be extended to explore current in parallel circuits, the effect of adding more light bulbs and resistance.
Why not use these materials on careers in science journalism as the introduction to an activity investigating resistance?
The resource suggests several ways to use the careers video as a starter. Students then investigate the resistance changes in a filament and write a magazine article to explain why bulbs 'blow' when they are turned on, rather than when they are already lit.
This is an extensive and thorough resource and will take some time to read through - but well worth the effort.
Open the Teaching Activities file and you will find a good selection of ideas to help students to develop a model of how an electric circuit works and also to capture their interest. For example, the design and make activity challeges students to 'invent' a burglar alarm for the classroom door, a pressure pad alarm for a chair or steady-hand tester.
To add to the sense of occassion, ask a senior member of staff to come into the lesson and try out the alarmed chair!
The Physics Narrative and Teaching and Learning files will be particularly appreciated by those teaching outside of their specialism
It is useful for students to have a number of analogies which they can draw upon in order to develop a real understanding of electric circuits. Comparing the strengths and weaknesses of different analogies can help to clarify ideas and assess students' understanding. This interactive analogy relates abstract concepts (such as charge and energy) directly to familiar everyday objects (delivery vans, bread).
The analogy provides students with an accessible way of thinking about electric circuits, which they can use to support their predictions and explanations when investigating different apsects of circuits.
Including careers resources throughout the scheme of work is a good way to raise students' awareness of the huge range of careers which use science.
This short clip, useful as an introduction to a lesson on measuring current or voltage, features a student talking about her apprenticeship course in electrical installation at Exeter college. She describes the entry qualifications needed for her course, contrasts her experiences at college compared to school and briefly mentions health and safety considerations when working.
Voltage, or potential difference, can be a daunting area of the curriculum to teach, especially for non-specialists. This resource provides useful subject knowledge as well as suggested class activities.
The resource also details Teaching and Learning issues surrounding voltage and provides a range of strategies and teaching ideas. It offers advice on a route through the topic, starting by comparing a range of electrical appliances to introduce the idea of electrical power in a familiar context. This can lead into looking at domestic energy costs and fuel bills to provide context. .