3.2.8

Optical Fibres

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Optical Fibres

Optical fibres transmit light by total internal reflection.

Illustrative background for CladdingIllustrative background for Cladding ?? "content

Cladding

  • 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.
Illustrative background for Small critical angleIllustrative background for Small critical angle ?? "content

Small critical angle

  • 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).
Illustrative background for Long distancesIllustrative background for Long distances ?? "content

Long distances

  • 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.

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1Motion, Forces & Energy

1.1Physical Quantities & Measurement Techniques

1.2Motion

1.3Mass & Weight

1.4Density

1.5Forces: Effects of Forces

1.6Forces: Turning Effects of Forces

1.7Forces: Centre of Gravity

1.8Momentum

1.9Energy, Work, & Power: Energy

1.10Energy, Work & Power: Work

1.11Energy, Work & Power: Energy Resources

1.12Energy, Work & Power: Power

1.13Pressure

2Thermal Physics

3Waves

4Electricity & Magnetism

4.1Simple Phenomena of Magnetism

4.2Electrical Quantities: Electric Charge

4.3Electrical Quantities: Electric Current

4.4Electromotive Force & Potential Difference

4.5Electrical Quantities: Resistance

4.6Electrical Energy & Electrical Power

4.7Electric Circuits: Circuit Diagrams & Components

4.8Electric Circuits: Series & Parallel Circuits

4.9Electric Circuits: Action & Use

4.10Electrical Safety

4.11Electromagnetic Effects: Electromagnetic Induction

4.12Electromagnetic Effects: The A.C. Generator

4.13Magnetic Effect of a Current

4.14Force on a Current-Carrying Conductor

4.15Electromagnetic Effects: The D.C. Motor

4.16Electromagnetic Effects: The Transformer

5Nuclear Physics

6Space Physics

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