0 vote
Two trains of equal length are running on parallel lines in the same direction at 54 km/hour and 36 km/hour. The faster train passes, the slower train in 18 seconds. the length of each train is:
Asked on by Guest | Votes 0 | Views: 21 | Tags: speed time and distance | quantitative aptitude | Add Bounty
Two trains of equal length are running on parallel lines in the same direction at 54 km/hour and 36 km/hour. The faster train passes, the slower train in 18 seconds. the length of each train is:
1). 90 m
2). 45 m
3). 72.2 m
4). 81 m
1 answers
3 vote
As they are in the same direction,
Relative velocity = 54 – 36 = 18 km/h = 5m/s
This means that the situation is the same as one train moving at 18km/h past another train that is at rest.
⇒ The distance covered on passing the entire train = length of the moving train + length of the stationary train = 2l ----(1)
Time taken = 18 sec ----(2)
∴ Distance = Speed × Time
⇒ 2l = 5 × 18
Thus, length of each train is 45m.