Question

train runs at a speed of 72 km per hour it crosses a pole in 25 seconds find the length of the train

Answer 1

speed=72km/h=72×5/18=20m/s
time =25 sec
lenght of train=distance travelled by train in 25 sec
lenght of train=speed ×time=20×25=500m

Answer 2

Speed Given=72km/hr
Given Time=25 seconds=1/144 hr
Therefore length of the train is = Speed*time=( 72*1/144)km=1/2km=500m
Hope I have Helped You!