PHYSICS CH6 Light — Science STD 9 — Question

• Optical fibres are extensively used for transmitting audio and video signals through long distances.
• Optical fibres too make use of the phenomenon of total internal reflection.
• Optical fibers are fabricated with high-quality composite glass/quartz fibres.
  Each fibres consists of a core and cladding. The refractive index of the material of the core is higher than that of the cladding.

When a signal in the form of light is directed at one end of the fibre at a suitable angle, it undergoes repeated total internal reflection along the length of the fibre and finally comes out at the other end. Optical fibres are extensively used for transmitting and receiving electrical signals which are converted to light between the ends of the fibre, over long distances.