Question

length of the train is 170 meters and speed of the train is 63 km/hour. this train can pass a bridge in 30 seconds, then find the length of the bridge.

Answer 1

63 × 5
--------- = 17.5 m/s
18

bridge length = ( speed × time ) - train length

17.5 × 30

= 525 - 170

= 355 m

Answer 2

Answer:

The length of the bridge is 355 meters.

Step-by-step explanation:

Length of the train is 170 meters

speed of the train is 63 km/h = 63 × 5/18 = 35/2 m/s

time taken to cross the bridge is 30 seconds

Now, we know that the distance traveled by a train to cross a bridge is equal to the sum of the lengths of the train and the bridge.

Let x be the length of the bridge.

Hence, distance traveled by train  = 170 +x

Therefore, we have

$\text{Speed }=\frac{\text{Distance}}{\text{Time}}\\\\\frac{35}{2}=\frac{170+x}{30}\\\\170+x=35\cdot15\\\\170+x=525\\x=355$

Hence, the length of the bridge is 355 meters.