Source: https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-8-internal-reflection-and-fibre-optics

[Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [A Level](https://senecalearning.com/en-gb/revision-notes/a-level.md) › [Physics](https://senecalearning.com/en-gb/revision-notes/a-level/physics.md) › [AQA](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa.md) › Internal Reflection & Fibre Optics

# Internal Reflection & Fibre Optics

Physics: AQA A Level, topic 3.2.8

## Optical Fibres

Optical fibres transmit light by total internal reflection.

### Cladding

![Cladding](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/3.1.2%20Internal%20reflection/facade-cladding-2851853_640-min.jpg)

- Each fibre has a core of optically dense material that is covered by a layer of cladding with a much lower optical density. 
- This means that the boundary between the two materials has a very small critical angle.

### Small critical angle

![Small critical angle](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/3.1.2%20Internal%20reflection/background-3045402_640-min.png)

- Only light approaching the boundary at an angle that is very close to the normal (90 degrees to the boundary) will cross the boundary and be refracted (this light is lost).

### Long distances

![Long distances](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/3.1.2%20Internal%20reflection/pexels-photo-718002-min.jpeg)

- Most of the light will be totally internally reflected and continue to travel through the core.
- In this way, optical fibres can transmit light over very long distances.

## Pulse Broadening and Absorption

Pulse absorption can result in a loss of signal intensity. Pulse broadening can degrade the signal.

### Pulse broadening - material dispersion

![Pulse broadening - material dispersion](https://image-v2.cdn.app.senecalearning.com/courseImages/chemistry/10.3.1%20Using%20materials/fibre-1562702_640-min.jpg)

- Material dispersion is due to different wavelengths of light arriving at the end of a fibre at different times. 
- This is because the refractive index of the fibre changes with frequency.
- This results in the pulse being broadened.
- The consequence of this is that the signal is now degraded.
- Signals may now overlap with each other.
- To avoid material dispersion, monochromatic light can be used.

### Pulse broadening - modal dispersion

![Pulse broadening - modal dispersion](https://image-v2.cdn.app.senecalearning.com/2018-07/0a18813c-bd29-4490-a4cf-2818a9d61ce0/Broadband-Bandwidth-Fibre-Optic-Cables-Computer-.jpg)

- Modal dispersion is due to the different paths signals will take in a fibre. This means different parts of the signal will arrive at different times.
- This results in the pulse being broadened.
- The consequence of this broadening is that the signal is now degraded.
- Signals may now overlap with each other.
- A monomode fibre can be used to avoid modal dispersion.

### Pulse absorption

![Pulse absorption](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.3%20Hormones%20in%20reproduction/sponge-231922_640.jpg)

- A signal may be absorbed by the material.
- This results in a reduction in the signal's amplitude.

### Countering signal degradation

![Countering signal degradation](https://image-v2.cdn.app.senecalearning.com/2018-09/a5713dd3-6649-44de-a6b4-85a0137271f6/light-photons-fibre-optic.jpg)

- Signals can be boosted by repeaters to counteract the effects of absorption and broadening.

## Test yourself on Internal Reflection & Fibre Optics

- What happens when the critical angle of incidence is exceeded?
- What are the conditions for total internal reflection?
- What are the key features of an optic fibre?
- How is the cladding of an optic fibre different to the core?
- What is meant by the phrase "a coherent bundle of fibres"?

[Practise this topic for free](https://app.senecalearning.com/classroom/course/890da800-6a58-11e8-973c-cb81832c8407/section/f3980ee1-b16c-4202-9315-2696a6c0126f/session)

- Previous topic: [3.2.7 Refraction at a Plane Surface](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-7-refraction-at-a-plane-surface.md)
- Next topic: [3.2.9 End of Topic Test - Refraction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-9-end-of-topic-test-refraction.md)

## Physics: AQA A Level contents

### 1 Measurements & Errors
- 1.1 Measurements & Errors
  - [1.1.1 SI Base Units](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-1-si-base-units.md)
  - [1.1.2 Combining SI Units](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-2-combining-si-units.md)
  - [1.1.3 Prefixes of Units](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-3-prefixes-of-units.md)
  - [1.1.4 Standard Form](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-4-standard-form.md)
  - [1.1.5 Converting Units](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-5-converting-units.md)
  - [1.1.6 End of Topic Test - Units & Prefixes](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-6-end-of-topic-test-units-and-prefixes.md)
  - [1.1.7 Limitation of Physical Measurements](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-7-limitation-of-physical-measurements.md)
  - [1.1.8 Uncertainty](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-8-uncertainty.md)
  - [1.1.9 Estimation](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-9-estimation.md)
  - [1.1.10 End of Topic Test - Measurements & Errors](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-10-end-of-topic-test-measurements-and-errors.md)
  - [1.1.11 Diagnostic Misconceptions - Converting between SI](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-11-diagnostic-misconceptions-converting-between-si.md)
  - [1.1.12 Diagnostic Misconceptions - SI & Area/Volume](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/1-1-12-diagnostic-misconceptions-si-and-areavolume.md)

### 2 Particles & Radiation
- 2.1 Particles
  - [2.1.1 Atomic Model](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-1-atomic-model.md)
  - [2.1.2 Specific Charge, Protons & Neutron Numbers](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-2-specific-charge-protons-and-neutron-numbers.md)
  - [2.1.3 End of Topic Test - Atomic Model](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-3-end-of-topic-test-atomic-model.md)
  - [2.1.4 Isotopes](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-4-isotopes.md)
  - [2.1.5 Stable & Unstable Nuclei](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-5-stable-and-unstable-nuclei.md)
  - [2.1.6 End of Topic Test - Isotopes & Nuclei](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-6-end-of-topic-test-isotopes-and-nuclei.md)
  - [2.1.7 A-A* (AO3/4) - Stable & Unstable Nuclei](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-7-a-a-ao34-stable-and-unstable-nuclei.md)
  - [2.1.8 Particles, Antiparticles & Photons](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-8-particles-antiparticles-and-photons.md)
  - [2.1.9 Particle Interactions](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-9-particle-interactions.md)
  - [2.1.10 Classification of Particles](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-10-classification-of-particles.md)
  - [2.1.11 End of Topic Test - Particles & Interactions](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-11-end-of-topic-test-particles-and-interactions.md)
  - [2.1.12 Quarks & Antiquarks](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-12-quarks-and-antiquarks.md)
  - [2.1.13 Application of Conservation Laws](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-13-application-of-conservation-laws.md)
  - [2.1.14 End of Topic Test - Leptons & Quarks](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-14-end-of-topic-test-leptons-and-quarks.md)
  - [2.1.15 Exam-Style Question -  Radioactive Decay](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-1-15-exam-style-question-radioactive-decay.md)
- 2.2 Electromagnetic Radiation & Quantum Phenomena
  - [2.2.1 The Photoelectric Effect](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-2-1-the-photoelectric-effect.md)
  - [2.2.2 The Photoelectric Effect Explanation](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-2-2-the-photoelectric-effect-explanation.md)
  - [2.2.3 End of Topic Test - The Photoelectric Effect](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-2-3-end-of-topic-test-the-photoelectric-effect.md)
  - [2.2.4 Collisions of Electrons with Atoms](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-2-4-collisions-of-electrons-with-atoms.md)
  - [2.2.5 Energy Levels & Photon Emission](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-2-5-energy-levels-and-photon-emission.md)
  - [2.2.6 Wave-Particle Duality](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-2-6-wave-particle-duality.md)
  - [2.2.7 End of Topic Test - Absorption & Emission](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-2-7-end-of-topic-test-absorption-and-emission.md)
  - [2.2.8 Diagnostic Misconceptions - Electron Volts](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-2-8-diagnostic-misconceptions-electron-volts.md)
  - [2.2.9 Diagnostic Misconceptions - Converting eV & Joules](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/2-2-9-diagnostic-misconceptions-converting-ev-and-joules.md)

### 3 Waves
- 3.1 Progressive & Stationary Waves
  - [3.1.1 Progressive Waves](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-1-1-progressive-waves.md)
  - [3.1.2 Wave Speed & Phase Difference](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-1-2-wave-speed-and-phase-difference.md)
  - [3.1.3 Longitudinal & Transverse Waves](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-1-3-longitudinal-and-transverse-waves.md)
  - [3.1.4 End of Topic Test - Progressive Waves](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-1-4-end-of-topic-test-progressive-waves.md)
  - [3.1.5 Polarisation](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-1-5-polarisation.md)
  - [3.1.6 Stationary Waves](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-1-6-stationary-waves.md)
  - [3.1.7 Stationary Waves 2](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-1-7-stationary-waves-2.md)
  - [3.1.8 End of Topic Test - Polarisation & Stationary Wave](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-1-8-end-of-topic-test-polarisation-and-stationary-wave.md)
  - [3.1.9 A-A* (AO3/4) - Stationary Waves](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-1-9-a-a-ao34-stationary-waves.md)
- 3.2 Refraction, Diffraction & Interference
  - [3.2.1 Interference](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-1-interference.md)
  - [3.2.2 Interference 2](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-2-interference-2.md)
  - [3.2.3 End of Topic Test - Interference](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-3-end-of-topic-test-interference.md)
  - [3.2.4 Diffraction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-4-diffraction.md)
  - [3.2.5 Diffraction Gratings](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-5-diffraction-gratings.md)
  - [3.2.6 End of Topic Test - Diffraction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-6-end-of-topic-test-diffraction.md)
  - [3.2.7 Refraction at a Plane Surface](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-7-refraction-at-a-plane-surface.md)
  - [3.2.8 Internal Reflection & Fibre Optics](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-8-internal-reflection-and-fibre-optics.md)
  - [3.2.9 End of Topic Test - Refraction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-9-end-of-topic-test-refraction.md)
  - [3.2.10 Exam-Style Question - Waves](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/3-2-10-exam-style-question-waves.md)

### 4 Mechanics & Materials
- 4.1 Force, Energy & Momentum
  - [4.1.1 Scalars & Vectors](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-1-scalars-and-vectors.md)
  - [4.1.2 Vector Problems](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-2-vector-problems.md)
  - [4.1.3 End of Topic Test - Scalars & Vectors](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-3-end-of-topic-test-scalars-and-vectors.md)
  - [4.1.4 Moments](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-4-moments.md)
  - [4.1.5 Centre of Mass](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-5-centre-of-mass.md)
  - [4.1.6 End of Topic Test - Moments & Centre of Mass](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-6-end-of-topic-test-moments-and-centre-of-mass.md)
  - [4.1.7 Motion in a Straight Line](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-7-motion-in-a-straight-line.md)
  - [4.1.8 Graphs of Motion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-8-graphs-of-motion.md)
  - [4.1.9 Bouncing Ball Example](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-9-bouncing-ball-example.md)
  - [4.1.10 End of Topic Test - Motion in a Straight Line](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-10-end-of-topic-test-motion-in-a-straight-line.md)
  - [4.1.11 Acceleration Due to Gravity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-11-acceleration-due-to-gravity.md)
  - [4.1.12 Projectile Motion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-12-projectile-motion.md)
  - [4.1.13 Friction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-13-friction.md)
  - [4.1.14 Terminal Speed](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-14-terminal-speed.md)
  - [4.1.15 End of Topic Test - Acceleration Due to Gravity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-15-end-of-topic-test-acceleration-due-to-gravity.md)
  - [4.1.16 Newton's Laws](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-16-newtons-laws.md)
  - [4.1.17 Momentum](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-17-momentum.md)
  - [4.1.18 Momentum 2](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-18-momentum-2.md)
  - [4.1.19 End of Topic Test - Newton's Laws & Momentum](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-19-end-of-topic-test-newtons-laws-and-momentum.md)
  - [4.1.20 A-A* (AO3/4) - Newton's Third Law](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-20-a-a-ao34-newtons-third-law.md)
  - [4.1.21 Work & Energy](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-21-work-and-energy.md)
  - [4.1.22 Power & Efficiency](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-22-power-and-efficiency.md)
  - [4.1.23 Conservation of Energy](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-23-conservation-of-energy.md)
  - [4.1.24 End of Topic Test - Work, Energy & Power](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-24-end-of-topic-test-work-energy-and-power.md)
  - [4.1.25 Exam-Style Question - Forces](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-25-exam-style-question-forces.md)
  - [4.1.26 Diagnostic Misconceptions - Perpendicular Vectors](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-26-diagnostic-misconceptions-perpendicular-vectors.md)
  - [4.1.27 Diagnostic Misconceptions - Weight Acts Downwards](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-27-diagnostic-misconceptions-weight-acts-downwards.md)
  - [4.1.28 Diagnostic Misconceptions - Acceleration Direction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-28-diagnostic-misconceptions-acceleration-direction.md)
  - [4.1.29 Diagnostic Misconceptions - Stationary Objects](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-29-diagnostic-misconceptions-stationary-objects.md)
  - [4.1.30 Diagnostic Misconceptions - Action & Reaction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-30-diagnostic-misconceptions-action-and-reaction.md)
  - [4.1.31 Diagnostic Misconceptions - RF Direction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-31-diagnostic-misconceptions-rf-direction.md)
  - [4.1.32 Diagnostic Misconceptions - RF Acceleration](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-32-diagnostic-misconceptions-rf-acceleration.md)
  - [4.1.33 Diagnostic Misconceptions - Change in Momentum](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-1-33-diagnostic-misconceptions-change-in-momentum.md)
- 4.2 Materials
  - [4.2.1 Density](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-2-1-density.md)
  - [4.2.2 Bulk Properties of Solids](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-2-2-bulk-properties-of-solids.md)
  - [4.2.3 Energy in Materials](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-2-3-energy-in-materials.md)
  - [4.2.4 Young Modulus](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-2-4-young-modulus.md)
  - [4.2.5 End of Topic Test - Materials](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/4-2-5-end-of-topic-test-materials.md)

### 5 Electricity
- 5.1 Current Electricity
  - [5.1.1 Basics of Electricity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-1-basics-of-electricity.md)
  - [5.1.2 Current-Voltage Characteristics](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-2-current-voltage-characteristics.md)
  - [5.1.3 End of Topic Test - Basics of Electricity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-3-end-of-topic-test-basics-of-electricity.md)
  - [5.1.4 Resistivity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-4-resistivity.md)
  - [5.1.5 Superconductivity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-5-superconductivity.md)
  - [5.1.6 A-A* (AO3/4) - Superconductivity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-6-a-a-ao34-superconductivity.md)
  - [5.1.7 End of Topic Test - Resistivity & Superconductors](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-7-end-of-topic-test-resistivity-and-superconductors.md)
  - [5.1.8 Circuits](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-8-circuits.md)
  - [5.1.9 Power and Conservation](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-9-power-and-conservation.md)
  - [5.1.10 Potential Divider](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-10-potential-divider.md)
  - [5.1.11 Emf & Internal Resistance](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-11-emf-and-internal-resistance.md)
  - [5.1.12 End of Topic Test - Power & Potential](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-12-end-of-topic-test-power-and-potential.md)
  - [5.1.13 Exam-Style Question - Resistance](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-13-exam-style-question-resistance.md)
  - [5.1.14 Diagnostic Misconceptions - Constant Current](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-14-diagnostic-misconceptions-constant-current.md)
  - [5.1.15 Diagnostic Misconceptions - Potential Difference](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/5-1-15-diagnostic-misconceptions-potential-difference.md)

### 6 Further Mechanics & Thermal Physics (A2 only)
- 6.1 Periodic Motion (A2 only)
  - [6.1.1 Circular Motion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-1-1-circular-motion.md)
  - [6.1.2 Circular Motion 2](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-1-2-circular-motion-2.md)
  - [6.1.3 End of Topic Test - Circular Motion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-1-3-end-of-topic-test-circular-motion.md)
  - [6.1.4 Simple Harmonic Motion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-1-4-simple-harmonic-motion.md)
  - [6.1.5 Simple Harmonic Systems](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-1-5-simple-harmonic-systems.md)
  - [6.1.6 Energy in Simple Harmonic Motion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-1-6-energy-in-simple-harmonic-motion.md)
  - [6.1.7 Resonance](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-1-7-resonance.md)
  - [6.1.8 End of Topic Test - Simple Harmonic Motion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-1-8-end-of-topic-test-simple-harmonic-motion.md)
  - [6.1.9 A-A* (AO3/4) - Simple Harmonic Motion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-1-9-a-a-ao34-simple-harmonic-motion.md)
- 6.2 Thermal Physics (A2 only)
  - [6.2.1 Thermal Energy Transfer](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-1-thermal-energy-transfer.md)
  - [6.2.2 Thermal Energy Transfer Experiments](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-2-thermal-energy-transfer-experiments.md)
  - [6.2.3 Ideal Gases](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-3-ideal-gases.md)
  - [6.2.4 Ideal Gases 2](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-4-ideal-gases-2.md)
  - [6.2.5 Boyle's Law & Charles' Law](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-5-boyles-law-and-charles-law.md)
  - [6.2.6 Molecular Kinetic Theory Model](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-6-molecular-kinetic-theory-model.md)
  - [6.2.7 Molecular Kinetic Theory Model 2](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-7-molecular-kinetic-theory-model-2.md)
  - [6.2.8 End of Topic Test - Thermal Energy & Ideal Gases](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-8-end-of-topic-test-thermal-energy-and-ideal-gases.md)
  - [6.2.9 Exam-Style Question - Ideal Gases](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-9-exam-style-question-ideal-gases.md)
  - [6.2.10 Diagnostic Misconceptions - Material & Mass](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-10-diagnostic-misconceptions-material-and-mass.md)
  - [6.2.11 Diagnostic Misconceptions - No Energy](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/6-2-11-diagnostic-misconceptions-no-energy.md)

### 7 Fields & Their Consequences (A2 only)
- 7.1 Fields (A2 only)
  - [7.1.1 Fields](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-1-1-fields.md)
- 7.2 Gravitational Fields (A2 only)
  - [7.2.1 Newton's Law](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-2-1-newtons-law.md)
  - [7.2.2 Gravitational Field Strength](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-2-2-gravitational-field-strength.md)
  - [7.2.3 Gravitational Potential](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-2-3-gravitational-potential.md)
  - [7.2.4 Orbits of Planets & Satellites](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-2-4-orbits-of-planets-and-satellites.md)
  - [7.2.5 Escape Velocity & Synchronous Orbits](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-2-5-escape-velocity-and-synchronous-orbits.md)
  - [7.2.6 End of Topic Test - Gravitational Fields](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-2-6-end-of-topic-test-gravitational-fields.md)
- 7.3 Electric Fields (A2 only)
  - [7.3.1 Coulomb's Law](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-3-1-coulombs-law.md)
  - [7.3.2 Electric Field Strength](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-3-2-electric-field-strength.md)
  - [7.3.3 Electric Field Strength 2](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-3-3-electric-field-strength-2.md)
  - [7.3.4 Electric Potential](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-3-4-electric-potential.md)
  - [7.3.5 End of Topic Test - Electric Fields](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-3-5-end-of-topic-test-electric-fields.md)
  - [7.3.6 A-A* (AO3/4) - Electric and Gravitational Field](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-3-6-a-a-ao34-electric-and-gravitational-field.md)
- 7.4 Capacitance (A2 only)
  - [7.4.1 Capacitance](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-4-1-capacitance.md)
  - [7.4.2 Parallel Plate Capacitor](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-4-2-parallel-plate-capacitor.md)
  - [7.4.3 Energy Stored by a Capacitor](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-4-3-energy-stored-by-a-capacitor.md)
  - [7.4.4 Capacitor Discharge](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-4-4-capacitor-discharge.md)
  - [7.4.5 Capacitor Charge](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-4-5-capacitor-charge.md)
- 7.5 Magnetic Fields (A2 only)
  - [7.5.1 Magnetic Flux Density](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-1-magnetic-flux-density.md)
  - [7.5.2 End of Topic Test - Capacitance & Flux Density](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-2-end-of-topic-test-capacitance-and-flux-density.md)
  - [7.5.3 Moving Charges in a Magnetic Field](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-3-moving-charges-in-a-magnetic-field.md)
  - [7.5.4 Magnetic Flux & Flux Linkage](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-4-magnetic-flux-and-flux-linkage.md)
  - [7.5.5 Electromagnetic Induction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-5-electromagnetic-induction.md)
  - [7.5.6 Electromagnetic Induction 2](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-6-electromagnetic-induction-2.md)
  - [7.5.7 Alternating Currents](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-7-alternating-currents.md)
  - [7.5.8 Operation of a Transformer](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-8-operation-of-a-transformer.md)
  - [7.5.9 Magnetic Flux Density](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-9-magnetic-flux-density.md)
  - [7.5.10 End of Topic Test - Electromagnetic Induction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/7-5-10-end-of-topic-test-electromagnetic-induction.md)

### 8 Nuclear Physics (A2 only)
- 8.1 Radioactivity (A2 only)
  - [8.1.1 Rutherford Scattering](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-1-rutherford-scattering.md)
  - [8.1.2 Alpha & Beta Radiation](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-2-alpha-and-beta-radiation.md)
  - [8.1.3 Gamma Radiation](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-3-gamma-radiation.md)
  - [8.1.4 Radioactive Decay](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-4-radioactive-decay.md)
  - [8.1.5 Half Life](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-5-half-life.md)
  - [8.1.6 End of Topic Test - Radioactivity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-6-end-of-topic-test-radioactivity.md)
  - [8.1.7 Nuclear Instability](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-7-nuclear-instability.md)
  - [8.1.8 Nuclear Radius](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-8-nuclear-radius.md)
  - [8.1.9 Mass & Energy](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-9-mass-and-energy.md)
  - [8.1.10 Binding Energy](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-10-binding-energy.md)
  - [8.1.11 Induced Fission](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-11-induced-fission.md)
  - [8.1.12 Safety Aspects of Nuclear Reactors](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-12-safety-aspects-of-nuclear-reactors.md)
  - [8.1.13 End of Topic Test - Nuclear Physics](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-13-end-of-topic-test-nuclear-physics.md)
  - [8.1.14 A-A* (AO3/4) - Nuclear Fusion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/8-1-14-a-a-ao34-nuclear-fusion.md)

### 9 Option: Astrophysics (A2 only)
- 9.1 Telescopes (A2 only)
  - [9.1.1 Astronomical Telescopes](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-1-1-astronomical-telescopes.md)
  - [9.1.2 Reflecting Telescopes](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-1-2-reflecting-telescopes.md)
  - [9.1.3 Single Dish Radio Telescopes](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-1-3-single-dish-radio-telescopes.md)
  - [9.1.4 Large Diameter Telescopes](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-1-4-large-diameter-telescopes.md)
- 9.2 Classification of Stars (A2 only)
  - [9.2.1 Classification by Luminosity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-2-1-classification-by-luminosity.md)
  - [9.2.2 Absolute Magnitude](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-2-2-absolute-magnitude.md)
  - [9.2.3 Black Body Radiation](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-2-3-black-body-radiation.md)
  - [9.2.4 Stellar Spectral Classes](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-2-4-stellar-spectral-classes.md)
  - [9.2.5 Hertzsprung-Russell Diagrams](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-2-5-hertzsprung-russell-diagrams.md)
  - [9.2.6 Astronomical Objects](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-2-6-astronomical-objects.md)
- 9.3 Cosmology (A2 only)
  - [9.3.1 Doppler Effect](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-3-1-doppler-effect.md)
  - [9.3.2 Hubble's Law](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-3-2-hubbles-law.md)
  - [9.3.3 Quasars](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-3-3-quasars.md)
  - [9.3.4 Detecting Exoplanets](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/9-3-4-detecting-exoplanets.md)

### 10 Option: Medical Physics (A2 only)
- 10.1 Physics of the Eye (A2 only)
  - [10.1.1 Physics of Vision](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-1-1-physics-of-vision.md)
  - [10.1.2 Defects of Vision](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-1-2-defects-of-vision.md)
  - [10.1.3 Lenses](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-1-3-lenses.md)
  - [10.1.4 Correcting Defects of Vision](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-1-4-correcting-defects-of-vision.md)
- 10.2 Physics of the Ear (A2 only)
  - [10.2.1 Structure of the Ear](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-2-1-structure-of-the-ear.md)
  - [10.2.2 Sensitivity of the Ear](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-2-2-sensitivity-of-the-ear.md)
  - [10.2.3 Hearing Defects](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-2-3-hearing-defects.md)
- 10.3 Biological Measurement (A2 only)
  - [10.3.1 Electrocardiography (ECG)](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-3-1-electrocardiography-ecg.md)
- 10.4 Non-Ionising Imaging (A2 only)
  - [10.4.1 Ultrasound Imaging](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-4-1-ultrasound-imaging.md)
  - [10.4.2 Ultrasound Imaging 2](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-4-2-ultrasound-imaging-2.md)
  - [10.4.3 Fibre Optics & Endoscopy](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-4-3-fibre-optics-and-endoscopy.md)
  - [10.4.4 Magnetic Resonance Scanning](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-4-4-magnetic-resonance-scanning.md)
- 10.5 X-Ray Imaging (A2 only)
  - [10.5.1 Diagnostic X-Rays](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-5-1-diagnostic-x-rays.md)
  - [10.5.2 X-Ray Image Processing](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-5-2-x-ray-image-processing.md)
  - [10.5.3 Absorption of X-Rays](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-5-3-absorption-of-x-rays.md)
  - [10.5.4 CT Scanners](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-5-4-ct-scanners.md)
- 10.6 Radionuclide Imaging & Therapy (A2 only)
  - [10.6.1 Imaging Techniques](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-6-1-imaging-techniques.md)
  - [10.6.2 Half Life](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-6-2-half-life.md)
  - [10.6.3 Gamma Camera](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-6-3-gamma-camera.md)
  - [10.6.4 High Energy X-Rays](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-6-4-high-energy-x-rays.md)
  - [10.6.5 Radioactive Implants](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-6-5-radioactive-implants.md)
  - [10.6.6 Imaging Comparisons](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/10-6-6-imaging-comparisons.md)

### 11 Option: Engineering Physics (A2 only)
- 11.1 Rotational Dynamics (A2 only)
  - [11.1.1 Moment of Inertia](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-1-1-moment-of-inertia.md)
  - [11.1.2 Rotational Kinetic Energy](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-1-2-rotational-kinetic-energy.md)
  - [11.1.3 Rotational Motion](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-1-3-rotational-motion.md)
  - [11.1.4 Torque & Angular Acceleration](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-1-4-torque-and-angular-acceleration.md)
  - [11.1.5 Angular Momentum](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-1-5-angular-momentum.md)
  - [11.1.6 Angular Work & Power](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-1-6-angular-work-and-power.md)
- 11.2 Thermodynamics & Engines (A2 only)
  - [11.2.1 First Law of Thermodynamics](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-2-1-first-law-of-thermodynamics.md)
  - [11.2.2 Non-Flow Processes](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-2-2-non-flow-processes.md)
  - [11.2.3 p-V Diagrams](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-2-3-p-v-diagrams.md)
  - [11.2.4 Engine Cycles](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-2-4-engine-cycles.md)
  - [11.2.5 Second Law & Engines](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-2-5-second-law-and-engines.md)
  - [11.2.6 Reversed Heat Engines](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/11-2-6-reversed-heat-engines.md)

### 12 Option: Turning Points in Physics (A2 only)
- 12.1 Discovery of the Electron (A2 only)
  - [12.1.1 Cathode Rays](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-1-1-cathode-rays.md)
  - [12.1.2 Thermionic Electron Emission](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-1-2-thermionic-electron-emission.md)
  - [12.1.3 Electron Specific Charge](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-1-3-electron-specific-charge.md)
  - [12.1.4 Millikan's Experiment](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-1-4-millikans-experiment.md)
- 12.2 Wave-Particle Duality (A2 only)
  - [12.2.1 Newton's & Huygen's Theories of Light](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-2-1-newtons-and-huygens-theories-of-light.md)
  - [12.2.2 Electromagnetic Waves](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-2-2-electromagnetic-waves.md)
  - [12.2.3 Photoelectricity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-2-3-photoelectricity.md)
  - [12.2.4 Wave-Particle Duality](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-2-4-wave-particle-duality.md)
  - [12.2.5 Electron Microscopes](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-2-5-electron-microscopes.md)
- 12.3 Special Relativity (A2 only)
  - [12.3.1 Michelson-Morley Experiment](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-3-1-michelson-morley-experiment.md)
  - [12.3.2 Einstein's Theory of Special Relativity](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-3-2-einsteins-theory-of-special-relativity.md)
  - [12.3.3 Time Dilation](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-3-3-time-dilation.md)
  - [12.3.4 Length Contraction](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-3-4-length-contraction.md)
  - [12.3.5 Mass & Energy](https://senecalearning.com/en-gb/revision-notes/a-level/physics/aqa/12-3-5-mass-and-energy.md)