Answer 1

Construction:

1. An optical fibre consists of an extremely thin, transparent, and flexible core surrounded by an optically rarer flexible cover called cladding.
2. For protection, the whole system is coated by a buffer and a jacket
3. The entire thickness of the fibre is less than half an mm.
4. Many such fibres can be packed together in an outer cover.
   
             Construction of Optical fiber

Working:

1. Working of optical fibre is based on the principle of total internal reflection.
2. An optical signal (a ray of light) entering the core suffers multiple total internal reflections before emerging out after several kilometres.
3. The optical signal travels with the highest possible speed in the material.
4. The emerged optical signal has an extremely low loss in signal strength.
    
                             Working of Optical fibre