Two trains A and B are 100 m and 150 m long and are moving at one another at…
2023
Two trains A and B are 100 m and 150 m long and are moving at one another at 54 Km/hr and 36 Km/hr respectively. Arun is sitting on coach B1 of train A. Calculate the time taken by Arun to completely cross Train B.
- A.
10 s
- B.
6 s
- C.
4 s
- D.
8 s
Attempted by 8 students.
Show answer & explanation
Correct answer: B
Speed conversions: 54 km/h = 15 m/s; 36 km/h = 10 m/s.
Relative speed: Trains move towards each other, so relative speed = 15 + 10 = 25 m/s.
Distance Arun must cross: Arun sits on the front coach of train A, so he needs to pass the entire length of train B = 150 m.
Time calculation: Time = distance / relative speed = 150 / 25 = 6 s.
Answer: 6 s. Arun takes 6 seconds to completely cross train B.
Note: The value 10 s corresponds to the time for the two trains to completely pass each other (total length 250 m) at the same relative speed: 250 / 25 = 10 s. That is not what the question asks.