Indian Railways – Standard rail length (Meter Gauge): What is the standard length of rails adopted on M.G. (metre-gauge) track on Indian Railways?

Introduction / Context:The standard rail length is a key permanent-way parameter. It affects the number of joints, maintenance effort, thermal behavior, and riding quality. This question checks recall of the standard rail length historically adopted for metre-gauge (M.G.) track on Indian Railways.

Given Data / Assumptions:

• M.G. denotes metre-gauge track, nominal gauge 1000 mm.
• Options list common historical rail lengths used by Indian Railways for different gauges.
• We assume conventional fish-plated rail practice (pre-LWR/CWR context).

Concept / Approach:Indian Railways historically standardized rail lengths by gauge: Broad Gauge used about 42 ft (≈12.8 m), Metre Gauge used about 39 ft (≈11.89–12.0 m), and Narrow Gauge used shorter lengths. The choice balances manufacturing, handling, joint spacing, and thermal expansion limits.

Step-by-Step Solution:Identify the typical M.G. standard: approximately 12 m.Match with the closest imperial option: 39 ft equals 11.89 m (≈12 m).Therefore, select 39 ft (11.89 m).

Verification / Alternative check:Permanent-way manuals and question banks consistently cite ≈12 m (39 ft) as the M.G. standard, while B.G. commonly used 42 ft (12.8 m).

Why Other Options Are Wrong:

• 33 ft and 36 ft: below the usual M.G. standard length.
• 42 ft: typical of B.G., not M.G.
• None: incorrect because a correct option is present.

Common Pitfalls:Confusing B.G. and M.G. standards, or mixing later long-welded rail practices with historical standard lengths.

Final Answer:39 ft (11.89 m)