Hpw to do Q1?

Name: 1. An optical fibre has an inner glass core surrounded by an outer glass cladding. A ray of light is totally internally reflected down the fibre as shown, striking the walls at angle Oo. The refractive indices of the n2 cladding core and the cladding are 1.52 and 1.35 respectively. n1 core (a) Give a reason why the glass core is surrounded by an outer glass cladding. (b) Find the critical angle of the core-cladding interface. (c) What is the maximum angle of incidence at P so that total internal reflection occurs at Q ? (d) The fibre is 2 km long. Find the longest time for light to travel from one end to the other