Given: Train running at 120 km/hr and crosses a pole in 9 seconds Formula Used: speed of train = distance/time Distance = length of train Speed of the train is given in km/h while time is given in seconds so first we need to convert speed into m/s because length has been asked in m To convert speed km/h into m/s multiply given speed with 5/18 and to convert speed m/s to km/h multiply given speed with 18/5 Calculation: ⇒ Speed in m/s = 120 km/hr × (5/18) = (100/3) m/s ⇒ Distance = (100/3) × 9 = 300 m ∴ Length of train = 300 m