Question

    Two trains of same length are running in parallel tracks in the same direction with speed 90 km/hr and 120 km/hr respectively. The latter completely crosses the former in 30 seconds. Find the length of each train (in m).

    A 150 m Correct Answer Incorrect Answer
    B 100 m Correct Answer Incorrect Answer
    C 125 m Correct Answer Incorrect Answer
    D 225 m Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    When two trains cross each other, they cover distance equal to the sum of their lengths with relative speed.  Let's take length of each train = x So, total length of both trains = 2x Relative speed = (120 – 90) × (5/18) = 25/3 m/sec. ∴  Total length = Time × Relative speed  ⇒  2x = (30 × 25)/3 ⇒  x = 125 m

    Practice Next