38
Train A of length 100 m crosses a pole in 4 seconds. Train B approaching towards train A with a speed of 15 m/sec crosses it in 9.1 seconds. Find the length of train B
- A264 m
- B200 m
- C250 m
- D260 m
Answer not set
Discussion 1
Log in or create a free account to reply and vote.
0
CCommunity
For Train A,
Speed = 100/4 = 25 m/s
Let the length of Train B be ‘x’
When the two trains cross each other by approaching each other,
Relative Speed = Sum of the speeds = 25 + 15 = 40 m/s
Distance = 100 + x
Time = 9.1 s
Speed = Distance/Time
∴ 40 = (100 + x)/9.1
∴ x + 100 = 364
∴ x = 264
∴ The length of the 2nd train is 264 m
Speed = 100/4 = 25 m/s
Let the length of Train B be ‘x’
When the two trains cross each other by approaching each other,
Relative Speed = Sum of the speeds = 25 + 15 = 40 m/s
Distance = 100 + x
Time = 9.1 s
Speed = Distance/Time
∴ 40 = (100 + x)/9.1
∴ x + 100 = 364
∴ x = 264
∴ The length of the 2nd train is 264 m