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NDA2015General AbilityGeneral ScienceActual

Optical fibres, though bent in any manner, allows light to pass through. What is the inference that one can draw from it ?

Options

  1. AThe concept that light travels in straight path is wrong
  2. BLight can flow through the optical fibres
  3. CLight can travel through the fibres because of their ductility
  4. DLight can travel through the fibres due to multiple total internal reflections

Correct answer

D. Light can travel through the fibres due to multiple total internal reflections

Step-by-step solution

Once the light enters the end of the tube or fibre, it experiences total internal reflection because of the large angle of incidence.

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