Two goods trains 132 m and 108 m in length are running towards each other on parallel tracks. The first train is running at a speed of 32 km/h and the second at a speed of 40 km/h. How much time will they take to cross each other after meeting?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 12 s.
The speeds of the two trains are 32 km/h and 40 km/h.
Relative speed = 32 km/h + 40 km/h
= 72 km/h
= 72 × (5/18) m/s
= 20 m/s
Total distance to be covered = 132 m + 108 m = 240 m
Time required = 240/20 = 12 sec
Therefore, the trains will take 12 seconds to cross each other.