Question

a 200m long train crosses a 400m long brige with a speed of 36km/hr calculate time takenby the train to cross the brige

Answer 1

HI !

Length of train = 200 m
Length of bridge = 400 m
Total distance covered = 400 + 200 = 600 m

[ Note : To convert km/hr to m/s , multiply it by 5/18 ]

Speed = 36 km/hr = 36*5/18 = 10 m/s 

Time = Distance/speed
         = 600/10
         = 60 sec
         = 1 min

Time taken by the train to cross the bridge = 1 min