Question

A train running at speed of 60kmph crosses a pole in 9 seconds, what is the length of train?

Answer 1

Answer:

a)Length of train = (60km/h*(9/(60*60))*1000m = 150 m

or

b)60km/h*(5/18)*9 = 150 m

Step-by-step explanation:

units are different, so we need to convert

in answer a) 9 seconds converted into hour  

9s/60 gives time in minutes, again divide by 60 gives time in hours. ie, 9/60/60 = 9/(60*60) = 9/3600hours

lenth of train = speed *time = (60km/h)*(9/3600)h = 0.15km

now converting to m by multiplying answer by 1000 = .15km*1000 = 150 m

in answer b) km/h can be simply converted to m/s by multiplying by 5/18 (obtained by 1000/3600)

so answer = 60km/h*(5/18) = 16.666 m/s

length of tarin = 16.666m/s*9s = 150m