Source: https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-7-fuses

[Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [BTEC](https://senecalearning.com/en-gb/revision-notes/btec.md) › [Science](https://senecalearning.com/en-gb/revision-notes/btec/science.md) › [Applied Science: BTEC Level 3](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3.md) › Fuses

# Fuses

Applied Science: BTEC Level 3 National Extended Diploma, topic 3.7.7

## Fuses and Circuit Breakers

Fuses and circuit breakers protect us from electrical appliances by stopping the flow of electric current flow if it gets too high. This stops the appliance overheating.

### Fuses

![Fuses](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/4.3.4%20Electric%20Safety/fuse-min.jpg)

- Fuses contain a thin wire that melts if the current flowing through an appliance is too high.
- This breaks the circuit and stops the flow of electric current.

### Circuit breakers

![Circuit breakers](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/4.3.4%20Electric%20Safety/circuit-breaker-min.jpg)

- Circuit breakers are special devices that switch off the flow of current if the current is higher than a certain value.
- Circuit breakers do the same job as fuses but can be used lots of times.

## Fuse Ratings and Circuit Breaker Settings

Fuses and Circuit Breakers must be chosen correctly to allow correct function.

### Fuse ratings

![Fuse ratings](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/4.3.4%20Electric%20Safety/fuse-ratings%20-%20Edited-min.jpg)

- Fuse ratings tell us the level where a fuse will begin to melt. The fuse chosen should have a value just above the normal current that an electrical appliance uses. 
 - For example, if the operating current is 3.9 A, and fuses with values of 3 A, 5 A or 13 A are available, the most suitable fuse is the 5 A fuse.

## Test yourself on Fuses

- Which of these is not a property of circuit breakers?
- What are the advantages of circuit breakers over fuses?
- Why is a 13 A fuse wrong to use for an appliance with a 3.9 A operating current?
- Which fuse should you use for an appliance with an operating current of 6.5A?
- What do you need to know to select an appropriate fuse for a kettle?

[Practise this topic for free](https://app.senecalearning.com/classroom/course/83e90d6d-8d3e-4e59-a2df-b5a5e1957f6c/section/d31fc493-5e4d-4f60-800f-2556da7f0183/session)

- Previous topic: [3.7.6 Domestic Uses of Electricity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-6-domestic-uses-of-electricity.md)
- Next topic: [4.1.1 Atom Economy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-1-1-atom-economy.md)

## Applied Science: BTEC Level 3 National Extended Diploma contents

### 1 Principles of Science I
- 1.1 Structure & Bonding
  - [1.1.1 Atomic Model](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-1-atomic-model.md)
  - [1.1.2 Electron Shells, Sub-Shells & Orbitals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-2-electron-shells-sub-shells-and-orbitals.md)
  - [1.1.3 Ionic Bonding](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-3-ionic-bonding.md)
  - [1.1.4 Representing Ionic Bonds](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-4-representing-ionic-bonds.md)
  - [1.1.5 Covalent Bonding](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-5-covalent-bonding.md)
  - [1.1.6 Representing Covalent Bonds](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-6-representing-covalent-bonds.md)
  - [1.1.7 Metallic Bonding](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-7-metallic-bonding.md)
  - [1.1.8 Intermolecular Forces](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-8-intermolecular-forces.md)
  - [1.1.9 Intermolecular Forces 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-9-intermolecular-forces-2.md)
  - [1.1.10 End of Topic Test - Bonding](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-10-end-of-topic-test-bonding.md)
  - [1.1.11 Relative Masses](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-11-relative-masses.md)
  - [1.1.12 The Mole](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-12-the-mole.md)
  - [1.1.13 Molar Calculations](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-13-molar-calculations.md)
  - [1.1.14 Molar Calculations 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-14-molar-calculations-2.md)
  - [1.1.15 Empirical & Molecular Formulae](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-15-empirical-and-molecular-formulae.md)
  - [1.1.16 Balanced Equations](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-16-balanced-equations.md)
  - [1.1.17 Percentage Yield](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-17-percentage-yield.md)
  - [1.1.18 End of Topic Test - Amount of Substance](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-18-end-of-topic-test-amount-of-substance.md)
- 1.2 Properties of Substances
  - [1.2.1 The Periodic Table](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-1-the-periodic-table.md)
  - [1.2.2 Ionisation Energy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-2-ionisation-energy.md)
  - [1.2.3 Factors Affecting Ionisation Energies](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-3-factors-affecting-ionisation-energies.md)
  - [1.2.4 Trends of Ionisation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-4-trends-of-ionisation.md)
  - [1.2.5 Trends in the Periodic Table](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-5-trends-in-the-periodic-table.md)
  - [1.2.6 Polarity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-6-polarity.md)
  - [1.2.7 Metals & Non-Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-7-metals-and-non-metals.md)
  - [1.2.8 Alkali Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-8-alkali-metals.md)
  - [1.2.9 Alkaline Earth Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-9-alkaline-earth-metals.md)
  - [1.2.10 Reactivity of Alkaline Earth Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-10-reactivity-of-alkaline-earth-metals.md)
  - [1.2.11 Redox](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-11-redox.md)
  - [1.2.12 Transition Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-12-transition-metals.md)
  - [1.2.13 Redox Reactions of Transition Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-13-redox-reactions-of-transition-metals.md)
- 1.3 Cell Structure & Function
  - [1.3.1 Introduction to Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-1-introduction-to-cells.md)
  - [1.3.2 Prokaryotes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-2-prokaryotes.md)
  - [1.3.3 Organelles of Eukaryotic Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-3-organelles-of-eukaryotic-cells.md)
  - [1.3.4 Organelles of Eukaryotic Cells 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-4-organelles-of-eukaryotic-cells-2.md)
  - [1.3.5 Organelles in Plant Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-5-organelles-in-plant-cells.md)
  - [1.3.6 Microscopy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-6-microscopy.md)
  - [1.3.7 End of Topic Test - Cell Structure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-7-end-of-topic-test-cell-structure.md)
- 1.4 Cell Specialisation
  - [1.4.1 Cell Specialisation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-4-1-cell-specialisation.md)
  - [1.4.2 Blood Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-4-2-blood-cells.md)
  - [1.4.3 Plant Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-4-3-plant-cells.md)
  - [1.4.4 Gametes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-4-4-gametes.md)
- 1.5 Tissue Structure & Function
  - [1.5.1 Human Gas Exchange](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-1-human-gas-exchange.md)
  - [1.5.2 Blood Vessels](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-2-blood-vessels.md)
  - [1.5.3 Atherosclerosis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-3-atherosclerosis.md)
  - [1.5.4 Skeletal Muscle](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-4-skeletal-muscle.md)
  - [1.5.5 Slow & Fast Twitch Fibres](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-5-slow-and-fast-twitch-fibres.md)
  - [1.5.6 Neurones](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-6-neurones.md)
  - [1.5.7 Speed of Transmission](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-7-speed-of-transmission.md)
  - [1.5.8 Action Potentials](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-8-action-potentials.md)
  - [1.5.9 End of Topic Test - Neurones & Action Potentials](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-9-end-of-topic-test-neurones-and-action-potentials.md)
  - [1.5.10 Synapses](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-10-synapses.md)
  - [1.5.11 Types of Synapse](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-11-types-of-synapse.md)
  - [1.5.12 Medical Application](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-12-medical-application.md)
  - [1.5.13 End of Topic Test - Synapses](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-13-end-of-topic-test-synapses.md)
  - [1.5.14 Chemical Brain Imbalances](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-14-chemical-brain-imbalances.md)
  - [1.5.15 Effect of Drugs on the Brain](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-15-effect-of-drugs-on-the-brain.md)
- 1.6 Working with Waves
  - [1.6.1 Progressive Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-1-progressive-waves.md)
  - [1.6.2 Wave Speed & Phase Difference](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-2-wave-speed-and-phase-difference.md)
  - [1.6.3 Longitudinal & Transverse Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-3-longitudinal-and-transverse-waves.md)
  - [1.6.4 Stationary Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-4-stationary-waves.md)
  - [1.6.5 Stationary Waves 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-5-stationary-waves-2.md)
  - [1.6.6 Applications of Stationary Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-6-applications-of-stationary-waves.md)
  - [1.6.7 Interference](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-7-interference.md)
  - [1.6.8 Diffraction](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-8-diffraction.md)
  - [1.6.9 Diffraction Gratings](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-9-diffraction-gratings.md)
  - [1.6.10 Application of Diffraction Gratings](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-10-application-of-diffraction-gratings.md)
- 1.7 Waves in Communication
  - [1.7.1 Refraction at a Plane Surface](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-1-refraction-at-a-plane-surface.md)
  - [1.7.2 Internal Reflection & Fibre Optics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-2-internal-reflection-and-fibre-optics.md)
  - [1.7.3 Applications of Total Internal Reflection](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-3-applications-of-total-internal-reflection.md)
  - [1.7.4 Properties](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-4-properties.md)
  - [1.7.5 Gamma, X-Ray & UV Light](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-5-gamma-x-ray-and-uv-light.md)
  - [1.7.6 Visible Light](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-6-visible-light.md)
  - [1.7.7 Infrared, Microwave & Radio Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-7-infrared-microwave-and-radio-waves.md)
  - [1.7.8 Intensity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-8-intensity.md)
  - [1.7.9 Digital & Analogue Signals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-9-digital-and-analogue-signals.md)
  - [1.7.10 Communication Channels](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-10-communication-channels.md)

### 2 Practical Scientific Procedures and Techniques
- 2.1 Titration
  - [2.1.1 pH Curves & Titrations](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-1-1-ph-curves-and-titrations.md)
  - [2.1.2 pH Curves & Titrations 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-1-2-ph-curves-and-titrations-2.md)
  - [2.1.3 Buffer Solutions](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-1-3-buffer-solutions.md)
- 2.2 Colorimetry
  - [2.2.1 Measuring Rates](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-2-1-measuring-rates.md)
  - [2.2.2 Beer-Lambert Law](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-2-2-beer-lambert-law.md)
- 2.3 Chromatography
  - [2.3.1 Overview of Chromatography](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-3-1-overview-of-chromatography.md)
  - [2.3.2 Thin-Layer Chromatography](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-3-2-thin-layer-chromatography.md)
  - [2.3.3 Column Chromatography](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-3-3-column-chromatography.md)
  - [2.3.4 Gas Chromatography](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-3-4-gas-chromatography.md)

### 3 Science Investigation Skills
- 3.1 Scientific Processes
  - [3.1.1 Aims, Hypotheses & Sampling](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-1-aims-hypotheses-and-sampling.md)
  - [3.1.2 Pilot Studies & Design](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-2-pilot-studies-and-design.md)
  - [3.1.3 Ethics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-3-ethics.md)
  - [3.1.4 Variables & Control](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-4-variables-and-control.md)
  - [3.1.5 Demand Characteristics & Investigator Effects](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-5-demand-characteristics-and-investigator-effects.md)
  - [3.1.6 Features of Science](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-6-features-of-science.md)
  - [3.1.7 Scientific Report](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-7-scientific-report.md)
  - [3.1.8 Scientific Report 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-8-scientific-report-2.md)
- 3.2 Data Handling & Analysis
  - [3.2.1 Types of Data](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-2-1-types-of-data.md)
  - [3.2.2 Descriptive Statistics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-2-2-descriptive-statistics.md)
  - [3.2.3 Presentation & Display of Data](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-2-3-presentation-and-display-of-data.md)
- 3.3 Enzymes in Action
  - [3.3.1 Overview of Protein Structure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-3-1-overview-of-protein-structure.md)
  - [3.3.2 Enzymes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-3-2-enzymes.md)
  - [3.3.3 Factors Affecting Enzyme Activity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-3-3-factors-affecting-enzyme-activity.md)
  - [3.3.4 Enzyme-Controlled Reactions](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-3-4-enzyme-controlled-reactions.md)
- 3.4 Diffusion
  - [3.4.1 Diffusion](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-4-1-diffusion.md)
- 3.5 Plants & Their Environment
  - [3.5.1 Factors Affecting Plant Growth](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-5-1-factors-affecting-plant-growth.md)
  - [3.5.2 Measuring Number & Distribution of Species](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-5-2-measuring-number-and-distribution-of-species.md)
- 3.6 Energy Content in Fuels
  - [3.6.1 Fractions](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-1-fractions.md)
  - [3.6.2 Burning Hydrocarbons](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-2-burning-hydrocarbons.md)
  - [3.6.3 Combustion](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-3-combustion.md)
  - [3.6.4 Energy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-4-energy.md)
  - [3.6.5 Energy at Home](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-5-energy-at-home.md)
  - [3.6.6 Calorimetry](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-6-calorimetry.md)
- 3.7 Electrical Circuits
  - [3.7.1 Circuit Diagrams & Components](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-1-circuit-diagrams-and-components.md)
  - [3.7.2 Diodes, LDRs & Thermistors](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-2-diodes-ldrs-and-thermistors.md)
  - [3.7.3 Resistance](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-3-resistance.md)
  - [3.7.4 Electrical Work](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-4-electrical-work.md)
  - [3.7.5 Ohm's Law](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-5-ohms-law.md)
  - [3.7.6 Domestic Uses of Electricity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-6-domestic-uses-of-electricity.md)
  - [3.7.7 Fuses](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-7-fuses.md)

### 4 Principles of Science II
- 4.1 Extracting Elements
  - [4.1.1 Atom Economy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-1-1-atom-economy.md)
- 4.2 Relating Properties to use of Substances
  - [4.2.1 Group 2 Chemistry](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-1-group-2-chemistry.md)
  - [4.2.2 End of Topic Test - Group 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-2-end-of-topic-test-group-2.md)
  - [4.2.3 Electrolysis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-3-electrolysis.md)
  - [4.2.4 Electrolysis Examples](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-4-electrolysis-examples.md)
  - [4.2.5 Extracting Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-5-extracting-metals.md)
  - [4.2.6 Transition Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-6-transition-metals.md)
  - [4.2.7 Variable Oxidation States](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-7-variable-oxidation-states.md)
  - [4.2.8 Heterogeneous Catalysts](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-8-heterogeneous-catalysts.md)
  - [4.2.9 Homogeneous Catalysts](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-9-homogeneous-catalysts.md)
- 4.3 Organic Chemistry
  - [4.3.1 Naming Compounds](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-1-naming-compounds.md)
  - [4.3.2 Functional Groups](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-2-functional-groups.md)
  - [4.3.3 Isomerism](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-3-isomerism.md)
  - [4.3.4 Hydrocarbons](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-4-hydrocarbons.md)
  - [4.3.5 Structure of Alkanes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-5-structure-of-alkanes.md)
  - [4.3.6 Boiling Points of Alkanes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-6-boiling-points-of-alkanes.md)
  - [4.3.7 Alkenes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-7-alkenes.md)
  - [4.3.8 Curly Arrows & Mechanisms](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-8-curly-arrows-and-mechanisms.md)
  - [4.3.9 Cracking](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-9-cracking.md)
  - [4.3.10 Combustion](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-10-combustion.md)
  - [4.3.11 Free Radical Substitution of Alkanes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-11-free-radical-substitution-of-alkanes.md)
  - [4.3.12 Electrophilic Addition of Alkenes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-12-electrophilic-addition-of-alkenes.md)
- 4.4 Energy Changes in Industry
  - [4.4.1 The Kelvin Scale](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-1-the-kelvin-scale.md)
  - [4.4.2 Enthalpy Changes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-2-enthalpy-changes.md)
  - [4.4.3 Calorimetry](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-3-calorimetry.md)
  - [4.4.4 Bond Enthalpies](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-4-bond-enthalpies.md)
  - [4.4.5 Hess' Law](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-5-hess-law.md)
- 4.5 The Circulatory System
  - [4.5.1 The Circulatory System](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-1-the-circulatory-system.md)
  - [4.5.2 Blood Vessels](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-2-blood-vessels.md)
  - [4.5.3 Blood Transfusion & the ABO Rhesus System](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-3-blood-transfusion-and-the-abo-rhesus-system.md)
  - [4.5.4 The Heart](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-4-the-heart.md)
  - [4.5.5 The Cardiac Cycle](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-5-the-cardiac-cycle.md)
  - [4.5.6 Cardiac Output](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-6-cardiac-output.md)
  - [4.5.7 Coordination of Heart Action](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-7-coordination-of-heart-action.md)
  - [4.5.8 Heart Dissection](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-8-heart-dissection.md)
  - [4.5.9 Controlling Heart Rate](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-9-controlling-heart-rate.md)
  - [4.5.10 Electrocardiograms](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-10-electrocardiograms.md)
  - [4.5.11 Cardiovascular Disease](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-11-cardiovascular-disease.md)
  - [4.5.12 Investigating Heart Rates](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-12-investigating-heart-rates.md)
- 4.6 Ventilation & Gas Exchange
  - [4.6.1 Human Gas Exchange](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-1-human-gas-exchange.md)
  - [4.6.2 Ventilation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-2-ventilation.md)
  - [4.6.3 Measuring Gas Exchange](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-3-measuring-gas-exchange.md)
  - [4.6.4 Controlling Ventilation Rate](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-4-controlling-ventilation-rate.md)
  - [4.6.5 Lung Disease](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-5-lung-disease.md)
  - [4.6.6 Lung Disease Data](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-6-lung-disease-data.md)
- 4.7 Urinary System
  - [4.7.1 Kidneys & Control of Water Balance](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-1-kidneys-and-control-of-water-balance.md)
  - [4.7.2 Kidneys & Osmoregulation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-2-kidneys-and-osmoregulation.md)
  - [4.7.3 Kidneys & Blood Pressure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-3-kidneys-and-blood-pressure.md)
  - [4.7.4 Urine](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-4-urine.md)
  - [4.7.5 Kidney Failure & Urinalysis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-5-kidney-failure-and-urinalysis.md)
  - [4.7.6 Dialysis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-6-dialysis.md)
  - [4.7.7 Transplants](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-7-transplants.md)
- 4.8 Cell Transport
  - [4.8.1 Cell Membrane Structure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-1-cell-membrane-structure.md)
  - [4.8.2 Diffusion](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-2-diffusion.md)
  - [4.8.3 Osmosis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-3-osmosis.md)
  - [4.8.4 Active Transport](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-4-active-transport.md)
- 4.9 Thermal Physics
  - [4.9.1 Power & Efficiency](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-1-power-and-efficiency.md)
  - [4.9.2 Work & Energy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-2-work-and-energy.md)
  - [4.9.3 Conservation of Energy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-3-conservation-of-energy.md)
  - [4.9.4 Pressure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-4-pressure.md)
  - [4.9.5 First Law of Thermodynamics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-5-first-law-of-thermodynamics.md)
  - [4.9.6 Second Law of Thermodynamics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-6-second-law-of-thermodynamics.md)
  - [4.9.7 Heat Engines, Heat Pumps & Refrigerators](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-7-heat-engines-heat-pumps-and-refrigerators.md)
  - [4.9.8 Non-Flow Processes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-8-non-flow-processes.md)
  - [4.9.9 p-V Diagrams](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-9-p-v-diagrams.md)
  - [4.9.10 Ideal Gases](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-10-ideal-gases.md)
  - [4.9.11 Ideal Gases 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-11-ideal-gases-2.md)
  - [4.9.12 Thermal Energy Transfer](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-12-thermal-energy-transfer.md)
  - [4.9.13 Thermal Energy Transfer Experiments](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-13-thermal-energy-transfer-experiments.md)
- 4.10 Materials
  - [4.10.1 Density](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-1-density.md)
  - [4.10.2 Stress & Strain](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-2-stress-and-strain.md)
  - [4.10.3 Properties of Materials](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-3-properties-of-materials.md)
  - [4.10.4 Elasticity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-4-elasticity.md)
  - [4.10.5 Plasticity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-5-plasticity.md)
  - [4.10.6 Energy in Materials](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-6-energy-in-materials.md)
  - [4.10.7 Young Modulus](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-7-young-modulus.md)
- 4.11 Fluids
  - [4.11.1 Fluid Flow](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-1-fluid-flow.md)
  - [4.11.2 Viscosity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-2-viscosity.md)
  - [4.11.3 Density](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-3-density.md)
  - [4.11.4 Continuity Equation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-4-continuity-equation.md)
  - [4.11.5 Bernoulli's Equation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-5-bernoullis-equation.md)
  - [4.11.6 Non-Newtonian Fluids](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-6-non-newtonian-fluids.md)

### 5 Contemporary Issues in Science
- 5.1 Contemporary Issues in Science
  - [5.1.1 Sustainability](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-1-sustainability.md)
  - [5.1.2 Genetic Engineering](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-2-genetic-engineering.md)
  - [5.1.3 Uses of Genetic Modification](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-3-uses-of-genetic-modification.md)
  - [5.1.4 Stem Cell Therapy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-4-stem-cell-therapy.md)
  - [5.1.5 Cloning](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-5-cloning.md)
  - [5.1.6 Cloning 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-6-cloning-2.md)
  - [5.1.7 Nanotechnology](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-7-nanotechnology.md)
  - [5.1.8 Ecosystems](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-8-ecosystems.md)
- 5.2 Analysing Scientific Information
  - [5.2.1 Validity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-2-1-validity.md)
  - [5.2.2 Peer Review](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-2-2-peer-review.md)
