alleryIn optical fibers, light travels by:
AReflection from outer surface
BRefraction only
CDiffraction
DRepeated total internal reflection at core-cladding boundary
Answer & Solution
Correct answer: D. Repeated total internal reflection at core-cladding boundary
**Optical fiber:** core (higher n) surrounded by cladding (lower n).
Light incident at angle > critical angle undergoes TIR at boundary, travels along fiber with very little loss.
Cable laid across oceans for telecom.
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