Medium
How many seconds will a train 100 metres long running at the rate of 36 km an hour take to pass a certain telegraph post?
Explanation
Explanation
Step 1: Convert the train's speed from km/h to m/s: 36 km/h × (5/18) = 10 m/s. Step 2: To pass a stationary telegraph post, the train only needs to cover a distance equal to its own length, 100 m. Step 3: Time = distance ÷ speed = 100 ÷ 10 = 10 seconds. So the train takes 10 seconds to pass the post.
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