Question

270 m long train running at 40.5 km/hr. How much will it to cross a tree

Answer 1

Speed = D/T
Speed = 40.5 km/hr
Distance = length of train which is 270 meters
NOTE that standard unit of speed is kilometre and hrs. So, convert 270 meters into kilometers...
270 meters into kilometre
270/1000 = 0.270 kilometers
Now, Speed = D/T
40.5 km/hr = 0.270/T
T40.5 km/hr = 0.270
T = 0.270/40.5
T = 270/1000 × 10/405
T = 3/100
T = 0.03 hrs

or 24 sec

Answer 2

We know that speed = (distance /time)….

}=the distance is length of the train , so on rearranging above formula we get

=>Time=(length/speed)

THEREFORE

=(270)/(40.5*(5/18)) conversion of of speed from kmph to mps since length is in meters

So the answer is 24 sec