59 A light ray is travelling through a ring of an optical

Last updated: 5/29/2023

59 A light ray is travelling through a ring of an optical fibre which is made of four different glasses shown below but each part has the same geometrical thickness Their respective refractive indices are shown The light ray will take the maximum time in crossing the part 1 I Part I Part IV 1 51 1 52 1 54 1 53 Part II Part III 2 11 in all