In what time will a train 100 meters long cross an electric pole, if its speed be 144 km/hr.?
Given, Length of the train = 100 meter
Speed of the train = 144 km/hr.
= 144 x (5/18) meter/sec. = 40 meter/sec.
Since, Speed of the train = (Length of the train/ Time Taken to cross the pole)
Therefore, Time taken = (Length of train/Speed of the train)
= (100/40) Sec.
= 2.5 seconds.
Hence 2.5 seconds is the answer