Two trains 140 m and 160 m long run at the speed of 60 kmph and 40 kmph respectively in opposite directions on parallel tracks. The time (in seconds) which they take to cross each other, is:
10.8
Relative speed = (60 + 40) kmph =(100×518)m/sec =2509m/sec.
Distance covered in crossing each other = (140+160) m = 300m
Required time = (300×9250)sec =545sec = 10.8 seconds