1. Two trains are moving in opposite directions @ 60 km/hr and 90 km/hr. Their lengths are 1.10 km and 0.9 km respectively. The time taken by the slower train to cross the faster train in seconds is:
Relative speed = (60+ 90) km/hr
=
150 x
5
m/sec
18
=
125
m/sec.
3
Distance covered = (1.10 + 0.9) km = 2 km = 2000 m.
Required time =
2000 x
3
sec = 48 sec.
125