Question
Two trains P and Q of lengths 250 m and 400 m,
respectively, are running in the same direction on parallel tracks at 90 km/h and 120 km/h, respectively. How much time will the trains take to cross each other completely?Solution
Length of train P =250m and train Q=400m. Total distance =250+400=650m Speed of trains P and Q =90 km/h and 120 km/h. Speed of trains when are running in the same direction=120-90=30km/h =30×5/18=150m/18 sec. = 8.33 m/s Now time =650/8.33 =78sec.
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