Trains A and B are running in the same direction at 40 km/h and 60 km/h, respectively. If both the trains started at the same time from the same place, then what will be the distance between them after 1 hour ?

10 km 20 km 40 km 0 km

20 km

Relative speed ( when moves in same direction ) = ( 60 - 40 )km/h = 20 km/h Distance = Speed × Time  = 20 × 1 = 20 km