A train-K whose length is 200 m, passes a train-B (which is not moving) of 400 m long in 15 s. Find the speed of the train-K.
40 m/s
Distance travelled = Length of train-K + length of train-B
= 200 m + 400 m
= 600 m
Time taken to cross train-B = 15 s
∵ speed = distanceTime
⇒ Speed of train-K = 60015
= 40 m/s