A train of length 100 meters is moving at a speed of 70 km/hr. In what time it…
2026
A train of length 100 meters is moving at a speed of 70 km/hr. In what time it will cross a man who is walking at 10 km/hr in the same direction?
- A.
6 seconds
- B.
5 seconds
- C.
8 seconds
- D.
7 seconds
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Correct answer: A
Since the train and the man are moving in the same direction, we must use the relative speed of the train with respect to the man.
Speed of the train = 70 km/h, speed of the man = 10 km/h, so relative speed = 70 − 10 = 60 km/h.
Convert 60 km/h to m/s: 60 × 5/18 ≈ 16.67 m/s.
The train has to cover its own length (100 m) relative to the man, so time = distance ÷ speed = 100 ÷ 16.67 ≈ 6 seconds.
Therefore, the train crosses the man in 6 seconds.