A train, 130 m long is running at the speed of 45 km/hr crosses a bridge in 30 seconds. What is the length of the bridge?
A. 145 metres
B. 245 metres
C. 325 metres
D. 215 metres
Answer: Option B
The distance travelled by train to cross the bridges is equal to the total length of train and bridge.
Speed = 45 x 5/18 m/sec = 25/2 m/sec.
Time = 30 sec
Total Distance Travelled = (25/2) x 30 = 375 m
Length of the bridge = 375 -130= 245 m