A train 360 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 140 m long?

Given Data

• Train length = 360 m
• Bridge length = 140 m
• Train speed = 45 km/hr
• Required: time to pass the bridge completely

Step 1: Total distance to be covered
Distance = train length + bridge length = 360 + 140 = 500 m

Step 2: Convert speed to m/s
45 km/hr = 45 × (5/18) = 12.5 m/s

Step 3: Time = distance ÷ speed
t = 500 ÷ 12.5 = 40 s

Checks & Common Pitfalls

• When crossing a bridge or platform, add lengths.
• Do not forget to convert km/hr to m/s by multiplying by 5/18.
• Check arithmetic: 500/12.5 equals 40.

Final Answer
The train will pass the bridge in 40 s.