Question
Two trains 180 metres and 170 metres in length are
running towards each other on parallel tracks, one at the rate 50 km/hr and another at 40 km/hr. In how many seconds will they be clear of each other from the moment they meet?Solution
Required time = Sum of the lengths of trains / Relative speed Relative speed = 50 + 40 = 90 kmph = (90 × 5)/18 = 25 m/sec Required time = (180 + 170)/25 = 350/25 = 14 seconds
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