Topic: Optical Instrumentation
In a fiber-optic cable, which phenomenon occurs for signal to propagate along the inner core
- A. Modulation
- B. Reflection
- C. Refraction
- D. All of the above
Answer: B. Reflection
Explanation: An optical fiber has high refractive index for core ($n_1$) and low refractive index for cladding ($n_2$). Thus the propagation of wave inside the fibre is through total internal reflection.