Two trains are moving in opposite directions at speeds of 50 km/h and 80 km/h. The length of one train is 480 m. The time taken by them to cross each other is 28 seconds. The length (in m) of the other train, correct to 2 decimal places, is:
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 531.11
Speed of first train = 50 km/h = 50 × 5\18 = 13.8889 m/s
Speed of second train = 80 km/h = 80 × 5\18 = 22.2222 m/s
Relative speed = 13.8889 + 22.2222 = 36.1111 m/s
Time to cross each other = 28 s
Total length = Relative speed × Time = 36.1111 × 28 = 1011.11 m
Length of second train = Total length − Length of first train
= 1011.11 − 480
= 531.11 m