A man sees a train passing over a bridge 1 km long. The length of the train is half that of the bridge. If the train clears the bridge in 2 minutes, the speed of the train is

30 km/hr 45 km/hr 50 km/hr 60 km/hr

45 km/hr

Length of the bridge = 1km and length of the train = 1/2 of bridge i.e. 500m Speed = \(\frac{1500}{ 120}\) m/s Speed = \(\frac{25 }{ 2}\) m/s Speed in km/hr: \(\frac{25 }{ 2}\) x \(\frac{18 }{ 5}\) = 45 km/hr