Source: https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-3-isotopes

[Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [International A Level](https://senecalearning.com/en-gb/revision-notes/international-a-level.md) › [Physics](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics.md) › [Cambridge International](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international.md) › Isotopes

# Isotopes

Physics: Cambridge International A Level, topic 14.2.3

## Isotopes

Atoms of the same element always have the same number of protons (i.e. same atomic number). But, atoms of the same element can have different numbers of neutrons. We call these isotopes. Hydrogen has three isotopes:

### Protium

![Protium](https://image-v2.cdn.app.senecalearning.com/courseImages/chemistry/1.1.2%20-%20Model%20of%20the%20atom/Protium%20symbol%20(1)-min.jpg)

- Protium is a hydrogen atom with 1 proton and 0 neutrons.
- 99.98% of hydrogen atoms are protium.
- It is used in hydrogen fuel cells and the production of plastics.

### Deuterium

![Deuterium](https://image-v2.cdn.app.senecalearning.com/courseImages/chemistry/1.1.2%20-%20Model%20of%20the%20atom/Deuterium%20symbol%20(1)-min.jpg)

- Deuterium is a hydrogen atom with 1 proton and 1 neutron.
- Around 0.02% of hydrogen atoms are deuterium.
- It is used in nuclear fusion.

### Tritium

![Tritium](https://image-v2.cdn.app.senecalearning.com/courseImages/chemistry/1.1.2%20-%20Model%20of%20the%20atom/Tritium%20symbol-min.jpg)

- Tritium is a hydrogen atom with 1 proton and 2 neutrons. 
- It is very rare.
- It is used in thermonuclear fusion weapons.

## Nuclides

A nuclide is a type of isotope.

### Definition of a nuclide

![Definition of a nuclide](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/OCR%20Gateway/atom%20arrangement.jpg)

- A nuclide refers to a specific nucleus that contains a certain number of protons and neutrons.

### Example

![Example](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/5.1.2.1%20-%20Three%20carbon%20nuclides-min.png)

- A carbon nuclide with 6 protons and 6 neutrons is different to a carbon nuclide with 6 protons and 7 neutrons. But, both are isotopes of carbon.

## Carbon Dating

We can use our knowledge of isotopes to calculate the age of fossils.

### Radioactive carbon-14

![Radioactive carbon-14](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/5.1.2.1%20-%20Three%20carbon%20nuclides-min.png)

- All living organisms have the same amount of carbon-14 atoms as a percentage of all carbon isotopes.
- Once the organism dies, it no longer absorbs carbon from the atmosphere.
- Carbon-14 is radioactive and so will decay over a known half life.
 - So, the older a fossil is, the fewer carbon-14 isotopes it will contain and the less radiation it emits.

## Test yourself on Isotopes

- Isotopes of hydrogen
- Protium contains 0 neutrons and tritium contains 2 neutrons. How many more neutrons does tritium have than protium?
- Which of the following is NOT a naturally occurring isotope of carbon?
- Carbon Dating
- Explain how radioactive carbon-14 can be used to find the age of a fossil.

[Practise this topic for free](https://app.senecalearning.com/classroom/course/1b5bc325-d783-4d2c-99cd-5a7d913debfc/section/4d17cd2b-99d3-4911-bb4d-ad89c5b01a64/session)

- Previous topic: [14.2.2 Atomic Model](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-2-atomic-model.md)
- Next topic: [14.2.4 Stable & Unstable Nuclei](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-4-stable-and-unstable-nuclei.md)

## Physics: Cambridge International A Level contents

### 1 Physical Quantities & Units
- 1.1 Physical Quantities & Units
  - [1.1.1 Use of SI Units](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-1-1-use-of-si-units.md)
  - [1.1.2 SI Prefixes, Standard Form & Converting Units](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-1-2-si-prefixes-standard-form-and-converting-units.md)
  - [1.1.3 End of Topic Test - Units & Prefixes](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-1-3-end-of-topic-test-units-and-prefixes.md)
  - [1.1.4 Avogadro's Constant](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-1-4-avogadros-constant.md)
  - [1.1.5 Scalars & Vectors](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-1-5-scalars-and-vectors.md)
- 1.2 Errors & Uncertainty
  - [1.2.1 Measuring Length, Time & Volume](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-2-1-measuring-length-time-and-volume.md)
  - [1.2.2 Measuring Temperature](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-2-2-measuring-temperature.md)
  - [1.2.3 Circuit Measurements](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-2-3-circuit-measurements.md)
  - [1.2.4 Limitation of Physical Measurements](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-2-4-limitation-of-physical-measurements.md)
  - [1.2.5 Uncertainty](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-2-5-uncertainty.md)
  - [1.2.6 Estimation](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-2-6-estimation.md)
  - [1.2.7 Displaying Data](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-2-7-displaying-data.md)
  - [1.2.8 End of Topic Test - Measurements & Errors](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/1-2-8-end-of-topic-test-measurements-and-errors.md)

### 2 Kinematics
- 2.1 Equations of Motion
  - [2.1.1 Motion in a Straight Line](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/2-1-1-motion-in-a-straight-line.md)
  - [2.1.2 Graphs of Motion](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/2-1-2-graphs-of-motion.md)
  - [2.1.3 Bouncing Ball Example](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/2-1-3-bouncing-ball-example.md)
  - [2.1.4 End of Topic Test - Motion in a Straight Line](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/2-1-4-end-of-topic-test-motion-in-a-straight-line.md)
  - [2.1.5 Acceleration Due to Gravity](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/2-1-5-acceleration-due-to-gravity.md)

### 3 Dynamics
- 3.1 Momentum & Newton's Laws of Motion
  - [3.1.1 Mass & Inertia](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/3-1-1-mass-and-inertia.md)
  - [3.1.2 Newton's Laws](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/3-1-2-newtons-laws.md)
  - [3.1.3 Momentum](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/3-1-3-momentum.md)
  - [3.1.4 End of Topic Test - Newton's Laws & Momentum](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/3-1-4-end-of-topic-test-newtons-laws-and-momentum.md)
  - [3.1.5 A-A* (AO3/4) - Newton's Third Law](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/3-1-5-a-a-ao34-newtons-third-law.md)
- 3.2 Non-Uniform Motion
  - [3.2.1 Projectile Motion](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/3-2-1-projectile-motion.md)
- 3.3 Linear Momentum & Conservation
  - [3.3.1 Conservation of Momentum](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/3-3-1-conservation-of-momentum.md)

### 4 Force, Density & Pressure
- 4.1 Force, Density & Pressure
  - [4.1.1 Fields](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-1-fields.md)
  - [4.1.2 Force in Uniform Fields](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-2-force-in-uniform-fields.md)
  - [4.1.3 Friction](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-3-friction.md)
  - [4.1.4 Buoyancy](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-4-buoyancy.md)
  - [4.1.5 Terminal Speed](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-5-terminal-speed.md)
  - [4.1.6 End of Topic Test - Acceleration Due to Gravity](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-6-end-of-topic-test-acceleration-due-to-gravity.md)
  - [4.1.7 Centre of Mass](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-7-centre-of-mass.md)
  - [4.1.8 Forces & Equilibrium](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-8-forces-and-equilibrium.md)
  - [4.1.9 End of Topic Test - Scalars & Vectors](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-9-end-of-topic-test-scalars-and-vectors.md)
  - [4.1.10 Moments](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-10-moments.md)
  - [4.1.11 End of Topic Test - Moments & Centre of Mass](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-11-end-of-topic-test-moments-and-centre-of-mass.md)
  - [4.1.12 Density](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-12-density.md)
  - [4.1.13 Pressure](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/4-1-13-pressure.md)

### 5 Work, Energy & Power
- 5.1 Work, Energy & Power
  - [5.1.1 Work & Energy](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/5-1-1-work-and-energy.md)
  - [5.1.2 Power & Efficiency](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/5-1-2-power-and-efficiency.md)
  - [5.1.3 Conservation of Energy](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/5-1-3-conservation-of-energy.md)
  - [5.1.4 End of Topic Test - Work, Energy & Power](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/5-1-4-end-of-topic-test-work-energy-and-power.md)
- 5.2 Gravitational Fields
  - [5.2.1 Newton's Law](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/5-2-1-newtons-law.md)
  - [5.2.2 Gravitational Field Strength](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/5-2-2-gravitational-field-strength.md)
  - [5.2.3 Gravitational Potential](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/5-2-3-gravitational-potential.md)

### 6 Deformation of Solids
- 6.1 Materials
  - [6.1.1 Bulk Properties of Solids](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/6-1-1-bulk-properties-of-solids.md)
  - [6.1.2 Energy in Materials](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/6-1-2-energy-in-materials.md)
  - [6.1.3 Young Modulus](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/6-1-3-young-modulus.md)
  - [6.1.4 End of Topic Test - Materials](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/6-1-4-end-of-topic-test-materials.md)

### 7 Waves
- 7.1 Simple Harmonic Motion
  - [7.1.1 Simple Harmonic Motion](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-1-1-simple-harmonic-motion.md)
  - [7.1.2 Simple Harmonic Systems](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-1-2-simple-harmonic-systems.md)
  - [7.1.3 Energy in Simple Harmonic Motion](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-1-3-energy-in-simple-harmonic-motion.md)
  - [7.1.4 Resonance](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-1-4-resonance.md)
  - [7.1.5 End of Topic Test - Simple Harmonic Motion](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-1-5-end-of-topic-test-simple-harmonic-motion.md)
  - [7.1.6 A-A* (AO3/4) - Simple Harmonic Motion](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-1-6-a-a-ao34-simple-harmonic-motion.md)
  - [7.1.7 End of Topic Test - Gravitational Fields](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-1-7-end-of-topic-test-gravitational-fields.md)
- 7.2 Waves
  - [7.2.1 Progressive Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-1-progressive-waves.md)
  - [7.2.2 Intensity of Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-2-intensity-of-waves.md)
  - [7.2.3 Wave Speed & Phase Difference](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-3-wave-speed-and-phase-difference.md)
  - [7.2.4 Longitudinal & Transverse Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-4-longitudinal-and-transverse-waves.md)
  - [7.2.5 End of Topic Test - Progressive Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-5-end-of-topic-test-progressive-waves.md)
  - [7.2.6 Electromagnetic Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-6-electromagnetic-waves.md)
  - [7.2.7 Doppler Effect](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-7-doppler-effect.md)
  - [7.2.8 Sound Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-8-sound-waves.md)
  - [7.2.9 Measuring Sound Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-9-measuring-sound-waves.md)
  - [7.2.10 End of Topic Test - Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-10-end-of-topic-test-waves.md)
  - [7.2.11 Ultrasound Imaging](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-11-ultrasound-imaging.md)
  - [7.2.12 Ultrasound Imaging 2](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/7-2-12-ultrasound-imaging-2.md)

### 8 Superposition
- 8.1 Superposition
  - [8.1.1 Stationary Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-1-stationary-waves.md)
  - [8.1.2 Stationary Waves 2](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-2-stationary-waves-2.md)
  - [8.1.3 End of Topic Test - Stationary Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-3-end-of-topic-test-stationary-waves.md)
  - [8.1.4 A-A* (AO3/4) - Stationary Waves](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-4-a-a-ao34-stationary-waves.md)
  - [8.1.5 Interference](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-5-interference.md)
  - [8.1.6 Interference 2](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-6-interference-2.md)
  - [8.1.7 End of Topic Test - Interference](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-7-end-of-topic-test-interference.md)
  - [8.1.8 Diffraction](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-8-diffraction.md)
  - [8.1.9 Diffraction Gratings](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-9-diffraction-gratings.md)
  - [8.1.10 End of Topic Test - Diffraction](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/8-1-10-end-of-topic-test-diffraction.md)

### 9 Thermal Physics
- 9.1 Circular Motion
  - [9.1.1 Circular Motion](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-1-1-circular-motion.md)
  - [9.1.2 Circular Motion 2](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-1-2-circular-motion-2.md)
  - [9.1.3 End of Topic Test - Circular Motion](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-1-3-end-of-topic-test-circular-motion.md)
- 9.2 Thermal Physics
  - [9.2.1 Temperature](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-1-temperature.md)
  - [9.2.2 Measuring Temperature](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-2-measuring-temperature.md)
  - [9.2.3 Ideal Gas Law](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-3-ideal-gas-law.md)
  - [9.2.4 Ideal Gases](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-4-ideal-gases.md)
  - [9.2.5 Boyle's Law & Charles' Law](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-5-boyles-law-and-charles-law.md)
  - [9.2.6 Molecular Kinetic Theory Model](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-6-molecular-kinetic-theory-model.md)
  - [9.2.7 Molecular Kinetic Theory Model 2](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-7-molecular-kinetic-theory-model-2.md)
  - [9.2.8 Thermal Energy Transfer](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-8-thermal-energy-transfer.md)
  - [9.2.9 Thermal Energy Transfer Experiments](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-9-thermal-energy-transfer-experiments.md)
  - [9.2.10 End of Topic Test - Thermal Energy & Ideal Gases](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-10-end-of-topic-test-thermal-energy-and-ideal-gases.md)
  - [9.2.11 First Law of Thermodynamics](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/9-2-11-first-law-of-thermodynamics.md)

### 10 Communication
- 10.1 Communication Channels
  - [10.1.1 Communication Channels](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/10-1-1-communication-channels.md)
  - [10.1.2 Modulation](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/10-1-2-modulation.md)
  - [10.1.3 Attenuation](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/10-1-3-attenuation.md)
- 10.2 Digital Communication
  - [10.2.1 Digital & Analogue Signals](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/10-2-1-digital-and-analogue-signals.md)
  - [10.2.2 Representing Sound](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/10-2-2-representing-sound.md)

### 11 Electric Fields
- 11.1 Electric Fields
  - [11.1.1 Coulomb's Law](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-1-1-coulombs-law.md)
  - [11.1.2 Electric Field Strength](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-1-2-electric-field-strength.md)
  - [11.1.3 Electric Field Strength 2](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-1-3-electric-field-strength-2.md)
  - [11.1.4 Electric Potential](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-1-4-electric-potential.md)
  - [11.1.5 End of Topic Test - Electric Fields](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-1-5-end-of-topic-test-electric-fields.md)
  - [11.1.6 A-A* (AO3/4) - Electric and Gravitational Field](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-1-6-a-a-ao34-electric-and-gravitational-field.md)
- 11.2 Capacitance
  - [11.2.1 Capacitance](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-2-1-capacitance.md)
  - [11.2.2 Parallel Plate Capacitor](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-2-2-parallel-plate-capacitor.md)
  - [11.2.3 Energy Stored by a Capacitor](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-2-3-energy-stored-by-a-capacitor.md)
  - [11.2.4 Capacitor Discharge](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-2-4-capacitor-discharge.md)
  - [11.2.5 Capacitor Charge](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/11-2-5-capacitor-charge.md)

### 12 Current Electricity
- 12.1 Current Electricity
  - [12.1.1 Basics of Electricity](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-1-basics-of-electricity.md)
  - [12.1.2 Mean Drift Velocity](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-2-mean-drift-velocity.md)
  - [12.1.3 Current-Voltage Characteristics](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-3-current-voltage-characteristics.md)
  - [12.1.4 End of Topic Test - Basics of Electricity](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-4-end-of-topic-test-basics-of-electricity.md)
  - [12.1.5 Resistivity](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-5-resistivity.md)
  - [12.1.6 End of Topic Test - Resistivity & Superconductors](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-6-end-of-topic-test-resistivity-and-superconductors.md)
  - [12.1.7 Power and Conservation](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-7-power-and-conservation.md)
  - [12.1.8 Microphones](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-8-microphones.md)
  - [12.1.9 Components](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-9-components.md)
  - [12.1.10 Relays](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-10-relays.md)
  - [12.1.11 Strain Gauges](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-1-11-strain-gauges.md)
- 12.2 DC Circuits
  - [12.2.1 Circuits](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-2-1-circuits.md)
  - [12.2.2 Potential Divider](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-2-2-potential-divider.md)
  - [12.2.3 Emf & Internal Resistance](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-2-3-emf-and-internal-resistance.md)
  - [12.2.4 End of Topic Test - Power & Potential](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/12-2-4-end-of-topic-test-power-and-potential.md)

### 13 Magnetic Fields
- 13.1 Magnetic Fields
  - [13.1.1 Magnetic Flux Density](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-1-1-magnetic-flux-density.md)
  - [13.1.2 End of Topic Test - Capacitance & Flux Density](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-1-2-end-of-topic-test-capacitance-and-flux-density.md)
  - [13.1.3 Moving Charges in a Magnetic Field](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-1-3-moving-charges-in-a-magnetic-field.md)
  - [13.1.4 Magnetic Flux & Flux Linkage](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-1-4-magnetic-flux-and-flux-linkage.md)
  - [13.1.5 Electromagnetic Induction](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-1-5-electromagnetic-induction.md)
  - [13.1.6 Electromagnetic Induction 2](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-1-6-electromagnetic-induction-2.md)
  - [13.1.7 Magnetic Flux Density](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-1-7-magnetic-flux-density.md)
  - [13.1.8 Magnetic Resonance Scanning](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-1-8-magnetic-resonance-scanning.md)
- 13.2 Alternating Currents
  - [13.2.1 Alternating Currents](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-2-1-alternating-currents.md)
  - [13.2.2 Operation of a Transformer](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-2-2-operation-of-a-transformer.md)
  - [13.2.3 End of Topic Test - Electromagnetic Induction & AC](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-2-3-end-of-topic-test-electromagnetic-induction-and-ac.md)
  - [13.2.4 Rectification](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/13-2-4-rectification.md)

### 14 Modern Physics
- 14.1 Quantum Physics
  - [14.1.1 The Photoelectric Effect](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-1-the-photoelectric-effect.md)
  - [14.1.2 The Photoelectric Effect Explanation](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-2-the-photoelectric-effect-explanation.md)
  - [14.1.3 End of Topic Test - The Photoelectric Effect](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-3-end-of-topic-test-the-photoelectric-effect.md)
  - [14.1.4 Collisions of Electrons with Atoms](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-4-collisions-of-electrons-with-atoms.md)
  - [14.1.5 Energy Levels & Photon Emission](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-5-energy-levels-and-photon-emission.md)
  - [14.1.6 Wave-Particle Duality](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-6-wave-particle-duality.md)
  - [14.1.7 End of Topic Test - Absorption & Emission](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-7-end-of-topic-test-absorption-and-emission.md)
  - [14.1.8 Band Theory](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-8-band-theory.md)
  - [14.1.9 Diagnostic X-Rays](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-9-diagnostic-x-rays.md)
  - [14.1.10 X-Ray Image Processing](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-10-x-ray-image-processing.md)
  - [14.1.11 Absorption of X-Rays](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-11-absorption-of-x-rays.md)
  - [14.1.12 CT Scanners](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-1-12-ct-scanners.md)
- 14.2 Nuclear Physics
  - [14.2.1 Rutherford Scattering](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-1-rutherford-scattering.md)
  - [14.2.2 Atomic Model](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-2-atomic-model.md)
  - [14.2.3 Isotopes](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-3-isotopes.md)
  - [14.2.4 Stable & Unstable Nuclei](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-4-stable-and-unstable-nuclei.md)
  - [14.2.5 A-A* (AO3/4) - Stable & Unstable Nuclei](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-5-a-a-ao34-stable-and-unstable-nuclei.md)
  - [14.2.6 Alpha & Beta Radiation](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-6-alpha-and-beta-radiation.md)
  - [14.2.7 Gamma Radiation](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-7-gamma-radiation.md)
  - [14.2.8 Particles, Antiparticles & Photons](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-8-particles-antiparticles-and-photons.md)
  - [14.2.9 Quarks & Antiquarks](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-9-quarks-and-antiquarks.md)
  - [14.2.10 Particle Interactions](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-10-particle-interactions.md)
  - [14.2.11 Radioactive Decay](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-11-radioactive-decay.md)
  - [14.2.12 Half Life](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-12-half-life.md)
  - [14.2.13 End of Topic Test - Radioactivity](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-13-end-of-topic-test-radioactivity.md)
  - [14.2.14 Nuclear Instability](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-14-nuclear-instability.md)
  - [14.2.15 Mass & Energy](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-15-mass-and-energy.md)
  - [14.2.16 Binding Energy](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-16-binding-energy.md)
  - [14.2.17 A-A* (AO3/4) - Nuclear Fusion](https://senecalearning.com/en-gb/revision-notes/international-a-level/physics/cambridge-international/14-2-17-a-a-ao34-nuclear-fusion.md)
