On Indian Broad Gauge, gauge widening on curves is generally provided when the degree of curve is:
-
AMore than 3°
-
B3° or less
-
CBetween 3° and 4° only
-
DNot required on any curve
-
EMore than 1° on straight track
Answer
Correct Answer: More than 3°
Explanation
Introduction / Context:Gauge widening on sharp curves helps reduce flange binding and limits wheel/rail wear. It is a standard geometric correction applied on tighter curves in Indian Railways.
Given Data / Assumptions:
- Degree of curve is measured by standard railway convention.
- Broad Gauge practice is referenced.
- Typical threshold used in exams is around 3°.
Concept / Approach:
Tighter curves (higher degree) cause higher lateral forces and flange contact. A small intentional widening of gauge eases passage, especially for long-wheelbase rolling stock. Hence, beyond a threshold sharpness, widening is provided.
Step-by-Step Solution:
Recognize that need grows with curvature tightness.Adopt exam-standard threshold: provide widening for curves > 3°.Choose the option that states “More than 3°”.Verification / Alternative check:
Design tables specify actual widening versus degree; many texts quote 3° as the indicative starting point for BG, with greater widening as degree increases.
Why Other Options Are Wrong:
“3° or less” is usually unnecessary; “between 3° and 4° only” is too restrictive; “not required” is incorrect; “more than 1° on straight track” is nonsensical.
Common Pitfalls:
Confusing degree of curve with cant; applying excessive widening without checking limits and wheelbase considerations.
Final Answer:
More than 3°