Two trains are moving in opposite directions at speeds of 36 km/h and 54 km/h. If their lengths are 100 m and 150 m, respectively, how much time will they take to cross each other completely?
10 seconds
Since the trains move in opposite directions, their relative speed is \(36 + 54 = 90\) km/h.
Converting to m/s: \(90 \times \frac{5}{18} = 25\) m/s.
The total distance to be covered while crossing is the sum of both lengths: \(100 + 150 = 250\) m.
The time taken is \(\frac{250}{25} = 10\) seconds.
Hence, the trains take 10 seconds to cross each other completely.
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