Electricity | AQA GCSE Combined Science Trilogy Physics, Higher tier (8464)
Electricity
- 209 questions
- 11 subtopics
- Physics Paper 1
- Physics Paper 1
Electricity is examined in Physics Paper 1.
It covers circuit symbols, electrical charge and current, current, resistance and potential difference, ohmic conductors, filament lamps, diodes and thermistors, light-dependent resistors, and investigating resistance, current and potential difference in series and parallel, constructing circuits, and calculating in series circuits, direct and alternating potential difference, and mains electricity, power and efficiency, appliances, and the energy transferred by electrical work, power, and the power ratings of domestic appliances and the National Grid.
Sample questions from Electricity
Answer each one closed book first, then open the answer.
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Circuit symbols, electrical charge and current
What must a closed circuit include before electrical charge will flow round it?
Show the answer
A source of potential difference, such as a cell or a battery. -
Current, resistance and potential difference
State the word equation linking potential difference, current and resistance.
Show the answer
Potential difference = current × resistance. -
Ohmic conductors, filament lamps, diodes and thermistors
Name four components whose resistance is not constant.
Show the answer
A filament lamp, a diode, a thermistor and a light-dependent resistor. -
Light-dependent resistors, and investigating resistance
Which two quantities must be measured in order to determine the resistance of a component?
Show the answer
The potential difference across it and the current through it. -
Current and potential difference in series and parallel
What happens to the potential difference of the supply in a series circuit?
Show the answer
It is shared between the components in the circuit. -
Constructing circuits, and calculating in series circuits
Explain why adding a resistor in parallel decreases the total resistance of a circuit.
Show the answer
It provides an extra path for the charge, so more current flows from the supply for the same potential difference. -
Direct and alternating potential difference, and mains electricity
How many wires are there in the cable that connects most electrical appliances to the mains?
Show the answer
Three. -
Power and efficiency
Describe how the efficiency of an electric kettle could be increased.
Show the answer
By insulating the body of the kettle so that less energy is wasted warming the surrounding air.
The 11 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| Circuit symbols, electrical charge and current | Circuit symbols for cells, batteries, meters, resistors and diodes, where ammeters and voltmeters are connected, reading series and parallel circuit diagrams, closed circuits and electric current as a rate of flow of charge, the equation Q = It with its units and calculations, and why the current is the same all round a single loop. | 27 |
| Current, resistance and potential difference | What the current through a component depends on, potential difference and resistance, the equation V = IR with its rearrangement, units and calculations, investigating how the resistance of a wire depends on its length, and how adding resistors in series or in parallel changes the total resistance. | 20 |
| Ohmic conductors, filament lamps, diodes and thermistors | Constant and changing resistance, ohmic conductors at constant temperature and calculations with them, components whose resistance is not constant, why the resistance of a filament lamp rises as it heats, current against potential difference graphs for lamps and diodes, one-way current through a diode, and thermistors in thermostats and other uses. | 19 |
| Light-dependent resistors, and investigating resistance | How the resistance of a light-dependent resistor changes with brightness and where that is used, then the circuit, meters and variable resistor for measuring resistance and plotting current against potential difference. | 20 |
| Current and potential difference in series and parallel | The two ways of joining components and how to identify series and parallel circuits, how current and potential difference are shared in each, adding resistances in series with calculations, the total current drawn by a parallel circuit, and why resistors in parallel have a total resistance smaller than the smallest of them. | 19 |
| Constructing circuits, and calculating in series circuits | Building a circuit from its diagram and checking it, what happens when one lamp fails in series or parallel, why resistance adds in series, and calculating current and potential difference in series. | 17 |
| Direct and alternating potential difference, and mains electricity | Mains electricity as an alternating supply at 50 Hz and about 230 V, direct and alternating potential difference, the three-core cable with its colour-coded live, neutral and earth wires, the job and potential of each wire, and why the live wire is dangerous even when a switch is open. | 20 |
| Power and efficiency | Efficiency in terms of energy transfer and of power with calculations, ways of increasing the efficiency of machines, kettles and motors by reducing wasted energy, and power in terms of potential difference and current and as P = I²R, with the units each equation uses. | 20 |
| Appliances, and the energy transferred by electrical work | What everyday appliances are designed to do, the energy transfers in kettles, drills and toasters, how power and time decide the energy an appliance transfers, the work done when charge flows and why resistors warm up, and calculating energy transferred from power and time or from charge flow and potential difference. | 19 |
| Power, and the power ratings of domestic appliances | The units of energy, power, time, charge and potential difference in energy calculations, what the power of a circuit device means and how it relates to potential difference, current and energy transferred per second, power ratings on domestic appliances, and comparing the energy transferred by appliances of different power. | 16 |
| The National Grid | The National Grid as a system of cables and transformers, step-up and step-down transformers and why both are needed, energy wasted by the current heating transmission cables, and why transmitting at a high potential difference and low current makes the grid efficient. | 12 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby topics
AQA GCSE Combined Science Trilogy Physics, Higher tier Active Recall Guide
Every topic, not just this one. 1,093 questions with their answers.