Question

Two trains 140 m and 160 m long run at the speed of 60 km/hr and 40 km/hr respectively in opposite directions on parallel tracks. The time (in seconds) which they take to cross each other, is:

Answer 1

Relative speed of the two trains will be 60+40 = 100km/hr = 100*5/18 m/s = 250/9m/s

Distance covered by the trains in crossing each other= 140+160=300 m

Therefore time required = Distance/Speed = 300/250/9 =300*9/250 = 54/5 = 10.8sec