A train running at a speed 360 km/hr passes a platform with double length in 30 sec. Find the length of platform.

2 km

Speed of train = 360 km/hr = 360 × \(\frac{5}{18}\) m/sec = 100 m/sec

Time = 30 sec

Let length of train = T

Then length of platform = 2 × T

Total distance traveled by train to pass the platform = T + (2 × T)

Distance = Speed × Time

⇒ T + (2 × T) = 100 × 30

⇒ 3T = 3000

⇒ T = 1000m or 1km

Length of platform = 2 × T = 2 × 1= 2 km.