Optical Fibres

1 mark · Easy

Which statement best describes how light travels along an optical fibre?

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Correct option: Light is totally internally reflected at the core–cladding boundary.

Common mistakes: Confusing refraction with total internal reflection

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Marking points

B1 · 1 mark · Correct option selected: total internal reflection.

Worked solution

Light is kept inside the fibre by total internal reflection at the boundary between core and cladding.