Problems on Trains – Train length from pole time and speed: A train runs at 36 km/h and takes 8 seconds to pass a pole. What is the length of the train?

Difficulty: Easy

Correct Answer: 80 meters

Explanation:


Introduction / Context:
Passing a pole means covering the train’s length at the given speed. Convert speed to m/s to multiply by time and obtain length in metres.


Given Data / Assumptions:

  • Speed = 36 km/h = 10 m/s.
  • Time = 8 s.
  • Pole is a point.


Concept / Approach:
L_train = speed (m/s) * time (s).


Step-by-Step Solution:
L = 10 * 8 = 80 m.


Verification / Alternative check:
Converting back: 80 m at 10 m/s takes 8 s, matching the given time.


Why Other Options Are Wrong:
45, 48, 60, 288 m do not equal v * t with v = 10 m/s and t = 8 s.


Common Pitfalls:
Leaving speed in km/h and multiplying by seconds directly without conversion.


Final Answer:
80 meters

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