A train running at 72 km/h crosses a pole in 12 seconds. How much time(in seconds)will it take to cross a bridge 360 m long?

40 75 60 30

30

Speed = 72 × \(\frac{5}{18}\) = 20 m/sec Distance = Speed × Time = 20 × 12 = 240 m Total distance = 240 + 360 = 600 m Time taken = \(\frac{600}{20}\) = 30 sec