Difficulty: Easy
Correct Answer: 6.6 sec
Explanation:
Introduction / Context:
Crossing a point object (post/pole) requires the train to travel a distance equal to its own length at its running speed.
Given Data / Assumptions:
Concept / Approach:
Convert speed to m/s, then apply t = distance / speed = L / v.
Step-by-Step Solution:
Verification / Alternative check:
Scale check: if length doubled to 220 m, time would double to 13.2 s at same speed, which is consistent.
Why Other Options Are Wrong:
5, 5.6, 6.8, 7.2 s are off from L/v after correct conversion.
Common Pitfalls:
Using km/h directly with metres; confusing platform/bridge case with post case.
Final Answer:
6.6 sec
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