Question

A train travelling at 36 km/h crosses a pole in 25 seconds. How much time (in seconds) will it take to cross a bridge 250 m long?
1. 56
2. 72
3. 48
4. 50

Answer 1

Correct Answer - Option 4 : 50

Given :

Speed of train = 36 km/h

Time taken to cross a pole = 25 seconds

Length of bridge = 250 m

Formula used :

Distance = speed × time

Solution :

Speed of train = 36 × (5/18)

⇒ Speed of train = 10 m/s

⇒ Time taken = 25 seconds

⇒ Length of train = 25 × 10

⇒ Length of train = 250 m

⇒ Length of bridge = 250 m

⇒ Total length = length of tran + length of bridge

⇒ Total length = 250 + 250

⇒ Total length = 500 m

⇒ Time taken to cross the bridge = 500/10

∴ the time taken to cross the bridge is 50 second.