Identify the correct statements in the following.(A) Optical fibres c…

The correct answer is Option (2) → (A), (C) and (D) only

An optical fibre guides light by total internal reflection, which happens only when light in the denser medium meets the boundary at an angle larger than the critical angle.

(A) Optical fibres consist of a core and cladding — Correct. A glass or quartz core is surrounded by a cladding of lower refractive index.

(B) Optical fibres are fabricated such that light reflected at one side of the inner surface strikes the other at an angle smaller than the critical angle. — Incorrect. At an angle smaller than the critical angle the light would refract out of the core. The fibre is made so that the angle is larger than the critical angle.

(C) Optical fibres make use of the phenomenon of total internal reflection. — Correct. Repeated total internal reflections at the core-cladding boundary carry the light along the fibre with very little loss.

(D) Optical fibres can be used as an optical pipe — Correct. They carry light along curved paths, like a pipe, and are used as light pipes to view internal organs and to transmit signals.

NCERT (2026-27):
Total Internal Reflection in Nature and Its Technological Applications – “… Optical fibres too make use of the phenomenon of total internal reflection. Optical fibres are fabricated with high quality composite glass/quartz fibres. Each fibre consists of a core and cladding. … Optical fibres are fabricated such that light reflected at one side of inner surface strikes the other at an angle larger than the critical angle. Even if the fibre is bent, light can easily travel along its length. Thus, an optical fibre can be used to act as an optical pipe.”