What are the four Component 3 options, and what physics does each apply?
The options: an overview of the four Component 3 options (alternating currents, medical physics, the physics of sports, energy and the environment) and the core physics each one extends.
A focused answer to the structure of the Eduqas A-Level Physics Component 3 options, giving an overview of the four choices (alternating currents, medical physics, the physics of sports, and energy and the environment) and the core physics each one extends.
Reviewed by: AI editorial process; not yet individually human-reviewed
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What this dot point is asking
Eduqas Component 3 ends with one option chosen from four. Your school teaches one option to the whole class, and the final section of the Component 3 paper sets questions on that option only. This page gives an overview of all four options and the core physics each extends, so you can see how the option fits into the course; the most widely taught option, medical physics, has its own detailed page.
The answer
How the options work
Option A: Alternating currents
Option B: Medical physics
Options C and D
Examples in context
The options connect A-Level physics to real careers and issues: alternating currents to electrical and electronic engineering, medical physics to radiography and oncology, the physics of sports to sports science and biomechanics, and energy and the environment to the global challenge of clean power and climate change. Whichever option a school chooses, it shows students how the core physics they have learned applies to a field of professional and societal importance.
Try this
Q1. State how many options are studied for the Eduqas Component 3 exam. [1 mark]
- Cue. One option, chosen from four.
Q2. A sinusoidal voltage has a peak value of . Find its rms value. [2 marks]
- Cue. .
Q3. Name the four Component 3 options. [2 marks]
- Cue. Alternating currents, medical physics, the physics of sports, and energy and the environment.
Exam-style practice questions
Practice questions written in the style of WJEC Eduqas exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
Eduqas 20204 marksOption A (alternating currents): an alternating voltage has a peak value of . Calculate the root-mean-square voltage, and explain why the rms value is used for power calculations.Show worked answer →
Root-mean-square voltage: .
The rms value is used because it is the equivalent steady (DC) voltage that would deliver the same average power to a resistor. Since the instantaneous power varies through the cycle, using the peak value would overestimate the average power, while the rms value gives the correct mean power .
Markers reward , and explaining the rms value as the equivalent DC voltage delivering the same average power.
Eduqas 20224 marksOption D (energy and the environment): explain, in terms of wavelength, how the greenhouse effect traps energy in the Earth's atmosphere.Show worked answer →
The Sun is very hot, so by Wien's law it emits mostly short-wavelength (visible and near-infrared) radiation, which passes easily through the atmosphere and warms the Earth's surface.
The much cooler Earth re-radiates this energy at long (infrared) wavelengths. Greenhouse gases such as carbon dioxide and water vapour absorb strongly in the infrared, so they absorb the outgoing long-wavelength radiation and re-emit some of it back towards the surface, trapping energy and raising the surface temperature.
Markers reward the Sun emitting short-wavelength radiation that passes through, the Earth re-radiating at long (infrared) wavelengths, and greenhouse gases absorbing the infrared and re-emitting it back to the surface.
Related dot points
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A focused answer to the Eduqas A-Level Physics Component 3 medical physics option, covering the production and attenuation of X-rays, ultrasound imaging and acoustic impedance, PET scanning and positron annihilation, and the measurement of radiation dose and its biological effect.
- Nuclear decay: alpha, beta and gamma radiation and their properties, the random nature of decay, activity and the decay constant, the exponential decay law, and half-life.
A focused answer to the Eduqas A-Level Physics Component 3 nuclear decay content, covering the properties of alpha, beta and gamma radiation, the random nature of radioactive decay, activity and the decay constant, the exponential decay law N = N0 e^(-lambda t), and half-life.
- Nuclear energy: mass-energy equivalence, the mass defect and binding energy, binding energy per nucleon, and the energy released in nuclear fission and fusion.
A focused answer to the Eduqas A-Level Physics Component 3 nuclear energy content, covering mass-energy equivalence, the mass defect and binding energy, the binding energy per nucleon curve, and why both nuclear fission and fusion release energy.
- Particles and nuclear structure: the nuclear model of the atom, the classification of particles into hadrons and leptons, the quark model of protons and neutrons, and conservation laws in particle interactions.
A focused answer to the Eduqas A-Level Physics Component 3 particle physics content, covering the nuclear model of the atom, the classification of particles into hadrons and leptons, the quark model of protons and neutrons, and the conservation laws governing particle interactions.
Sources & how we know this
- Eduqas GCE AS/A Level Physics specification (A720QS) — WJEC Eduqas (2015)