Hard
Two trains of lengths 150 m and 100 m run on parallel tracks in opposite directions at 54 km/h and 36 km/h respectively. How long will they take to cross each other completely?
Explanation
Explanation
Step 1: The trains move in opposite directions, so their relative speed = 54 + 36 = 90 km/h.
Step 2: Convert to m/s: 90 × 5/18 = 25 m/s.
Step 3: To cross completely, the trains must cover the sum of their lengths = 150 + 100 = 250 m.
Step 4: Time = distance ÷ relative speed = 250 ÷ 25 = 10 seconds.
Answer: 10 seconds.
PRO TIP
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