Relative speed ( same direction )=|S1−S2| Distance = Speed × Time 1km∕hr=
5
18
m∕s When two trains cross each other, the total distance covered is the sum of their lengths (L1+L2). Calculation: Relative speed =75km∕hr−30km∕hr=45km∕hr Convert relative speed to m∕s : ⇒45km∕hr=45×
5
18
m∕s ⇒ Relative speed =
225
18
m∕s=
25
2
m∕s=12.5m∕s Let the length of the slow train be L2. Total distance =L1+L2=950+L2 meters Using Distance = Speed × Time: ⇒950+L2=12.5×108 ⇒950+L2=1350 ⇒L2=1350−950 ⇒L2=400m