WJEC GCSE Physics (Wales): complete guide to the units and the exams
A complete guide to WJEC GCSE Physics (specification 3420) for Wales. Covers Unit 1 (Electricity, Energy and Waves) and Unit 2 (Forces, Space and Radioactivity), how the two written papers and the practical assessment are structured, Foundation and Higher tiering, the recall equations, and how to revise each topic from 1.1 to 2.9.
WJEC GCSE Physics (specification 3420) is the separate (single) Physics GCSE for Wales, assessed by two written units and a practical assessment. The qualification is tiered into Foundation and Higher. This page is the index: below is a map of the two units, the exam structure, the practical assessment, and how to study each topic.
The two WJEC Physics units
The specification has two written units. Unit 1 covers topics 1.1 to 1.9; Unit 2 covers topics 2.1 to 2.9.
Unit 1: Electricity, Energy and Waves. Electric circuits, generating electricity, making use of energy, domestic electricity, the features of waves, total internal reflection, seismic waves, kinetic theory and electromagnetism.
Unit 2: Forces, Space and Radioactivity. Distance, speed and acceleration, Newton's laws, work and energy, momentum and stopping distances, stars and planets, the Universe, types of radiation, half-life, and nuclear decay and nuclear energy.
Exam structure
WJEC GCSE Physics is assessed by two written units and one practical assessment, and is tiered into Foundation (designed for grades C to G) and Higher (designed for grades A* to D, with an allowed E). A learner is entered for one tier only.
- Unit 1 (Electricity, Energy and Waves): 1 hour 45 minutes, 80 marks, 45%.
- Unit 2 (Forces, Space and Radioactivity): 1 hour 45 minutes, 80 marks, 45%.
- Unit 3 (Practical assessment): controlled assessment, 10%.
Each written paper assesses a range of question types, from short structured questions to extended quality of written communication (QWC) responses, including calculations and graph work. A formula list is printed at the start of each written paper, and a calculator is allowed throughout. Foundation candidates are not expected to rearrange equations.
Practical assessment
Unit 3 is a practical assessment worth 10% of the qualification, completed under controlled conditions. It draws on the specified practical work of the course, such as investigating the resistance and I-V characteristics of components, current and potential difference in circuits, force and extension for a spring, measuring specific heat capacity, and investigating waves. There is no separate practical written exam, but practical skills are also sampled in the two written papers through method, apparatus and analysis questions.
How to study WJEC Physics
Physics rewards confident calculation, precise definitions, and clear diagrams.
- Work from the specification statements. Each point from 1.1 to 2.9 is a checklist; questions are written from them.
- Drill the maths. With a large share of marks mathematical, selecting equations, substituting with units, and reading graphs must be automatic. Higher candidates must rearrange equations.
- Use the formula list well. Practise locating and applying the printed equations quickly, and learn which to choose.
- Master the practical work. The methods, apparatus and sources of error recur in Unit 3 and across both written papers.
- Match the command words. State and Describe want concise recall and observation; Explain wants a cause-and-effect chain; Evaluate wants a balanced judgement. Plan the longer QWC answers.
The two units, topic by topic
Each topic has specification-statement-level answer pages with worked exam questions and cross-links, plus an overview guide and a quiz. Browse the full set at /wjec-gcse/physics/syllabus.
For the official specification
WJEC publishes the full specification (3420), past papers and mark schemes at wjec.co.uk. Always revise from the current specification and WJEC's own past papers, because question style, the tiering and the formula list are board-specific.
Physics guides
In-depth written guides with paired practice quizzes.
- WJEC GCSE Physics electric circuits and electromagnetism overview
An overview of the electric circuits and electromagnetism content in Unit 1 of WJEC GCSE Physics (3420), mapping current, potential difference and resistance, series and parallel circuits, domestic electricity and safety, electromagnetism and the motor effect, and generators and transformers, with the key equations and how the topics are examined.
8 min readRead β - WJEC GCSE Physics forces and motion overview
An overview of the forces and motion topics (2.1 to 2.4) in Unit 2 of WJEC GCSE Physics (3420), mapping distance, speed and acceleration, Newton's laws, work and energy, momentum, and stopping distances, with the key equations and how each part is examined.
7 min readRead β - WJEC GCSE Physics generating electricity and energy overview
An overview of the generating electricity and energy content in Unit 1 of WJEC GCSE Physics (3420), mapping energy resources and power stations, the National Grid and transformers, energy transfer and efficiency, and reducing energy loss in the home, with the key ideas and how the topics are examined.
8 min readRead β - WJEC GCSE Physics kinetic theory overview
An overview of topic 1.8 Kinetic theory in Unit 1 of WJEC GCSE Physics (3420), mapping the particle model and changes of state, gas pressure and temperature, and specific heat capacity and latent heat, with the key equations and how the topic is examined.
7 min readRead β - WJEC GCSE Physics radioactivity and nuclear energy overview
An overview of the radioactivity topics (2.7 to 2.9) in Unit 2 of WJEC GCSE Physics (3420), mapping types of radiation, half-life, and nuclear fission and fusion, with the key properties and how each part is examined.
7 min readRead β - WJEC GCSE Physics space and the Universe overview
An overview of the space topics (2.5 and 2.6) in Unit 2 of WJEC GCSE Physics (3420), mapping the solar system and stars, the life cycle of stars, and the Universe with red shift and the Big Bang, and how each part is examined.
7 min readRead β - WJEC GCSE Physics waves overview
An overview of the waves content in Unit 1 of WJEC GCSE Physics (3420), mapping the features of waves, the electromagnetic spectrum, reflection, refraction and total internal reflection, and seismic waves, with the wave equation and how the topics are examined.
8 min readRead β
Physics practice quizzes
Multiple-choice drills with worked answer explanations. Your scores stay on this device.
- WJEC GCSE Physics electric circuits and electromagnetism overview quiz15 questionsStart β
- WJEC GCSE Physics forces and motion overview quiz15 questionsStart β
- WJEC GCSE Physics generating electricity and energy overview quiz15 questionsStart β
- WJEC GCSE Physics kinetic theory overview quiz14 questionsStart β
- WJEC GCSE Physics radioactivity and nuclear energy overview quiz14 questionsStart β
- WJEC GCSE Physics space and the Universe overview quiz14 questionsStart β
- WJEC GCSE Physics waves overview quiz15 questionsStart β
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