Optical fibre cables are used for high-speed and long-distance data transmission. Splicing of optical fibres means:

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Correct — C, joining of optical fibres. Splicing is the permanent joining of two fibre ends so that light crosses the junction with minimal loss. It is done either by fusion splicing — the two cleaved ends are aligned and melted together with an electric arc — or by mechanical splicing, where the ends are held aligned in a sleeve with an index-matching gel. Long-haul cables have to be built from fibre lengths of limited size, so splices are what turn many spools into one continuous link; a splice is permanent and has lower insertion loss than a removable connector.

Why the other options are wrong — (a) Bending is not a joining operation — and excessive bending is a defect, not a technique: macrobends and microbends let light escape the core, causing 'bend loss'. Installation standards specify a minimum bend radius for exactly this reason.  (b) Drawing is a manufacturing step, not a field operation: fibre is drawn (pulled) from a heated glass preform in a drawing tower to produce the hair-thin fibre in the first place. It happens before the cable ever reaches the site.  (d) The controlled cut of a fibre has its own name — cleaving, done with a cleaver to leave a flat, perpendicular end face. Cleaving is the preparation step just before splicing, not splicing itself.

Concept: An optical fibre guides light by total internal reflection: a glass core of higher refractive index is surrounded by cladding of lower refractive index, so light striking the boundary beyond the critical angle is reflected back into the core and travels the length of the fibre. Because fibre is manufactured and shipped in finite lengths, a real network is assembled by joining lengths end to end — permanently by splicing, or removably by connectors. Every joint costs some signal (splice loss), so the alignment quality of the joint is what decides link performance over long distances.

State PCS 2026 Q38 — Science & Technology PYQ with Answer

State PCS 2026 Q38 — Science & Technology PYQ with Answer