Problems on Trains – Time to pass a fixed point (single length used): A 110 m long train runs at 36 km/h. How long will it take to pass a fixed point (e.g., a signal post)?

Difficulty: Easy

Correct Answer: 11 sec.

Explanation:

Introduction / Context:To pass a fixed point, the train covers its own length at its running speed. Convert speed to m/s and divide train length by that speed to obtain time.

Given Data / Assumptions:

  • L_train = 110 m.
  • Speed = 36 km/h = 10 m/s.

Concept / Approach:Time = distance / speed = L_train / v.

Step-by-Step Solution:v = 36 * (1000/3600) = 10 m/s.t = 110 / 10 = 11 s.

Verification / Alternative check:At 10 m/s, in 11 s the train covers 110 m, exactly its length, thus fully clearing the point.

Why Other Options Are Wrong:12, 13, 15, 9 s are not equal to 110/10.

Common Pitfalls:Adding platform/tunnel length when none exists; mis-converting km/h to m/s.

Final Answer:11 sec.

Discussion & Comments

No comments yet. Be the first to comment!
Join Discussion