Question

two trains having length of 140 M and 160 M are running Parallel at the speed of 54 km / hour and 72 km/ hour respectively. in how much time will they pass each other completely

Answer 1

Let the speed of 140M train is zero then the speed of other train is (72-54)=18km/h = 5 m/s and it has to cover a distance of 180m
now, 180/5 =36 sec