A train X of length 345 m running at 50km/h crosses another train Y running at 76 km/h in the opposite direction in 22 seconds. Train Y will cross a bridge of length 905 m in:
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 63 seconds.
Given:
A train X of length 345 m running at 50km/h crosses another train Y running at 76 km/h in the opposite direction in 22 seconds
Length of bridge = 905 m
Calculations:
m/s = Km/h × 5/18
⇒ 50 km/h = 50 km/h × 5/18 = 125/9 m/s
⇒ 76 km/h = 76 km/h × 5/18 = 190/9 m/s
When any vehicles travel in opposite directions the relative speed will be the addition of their speed
Relative speed = 125/9 + 190/9 = 315/9 = 35 m/s
Total length of train X and Y = 22 × 35 = 770 m
Length of train Y = 770 - 345 = 425 m
Total length when crossing the bridge = 905 + 425 = 1330
Required time taken = 1330 ÷ (190/9) = 63 seconds