Multiple choice

A 120 m long train is moving towards West at a speed of 10 m/s. A bird is flying towards East at a speed of 5 m/s. What is the time taken by the bird to cross the train?

  1. 4 s

  2. 8 s

  3. 12 s

  4. 24 s
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B Correct answer
Explanation

Since the train and the bird are moving in opposite directions, their relative speed is the sum of their speeds: 10 m/s + 5 m/s = 15 m/s. The time taken to cross is the length of the train divided by the relative speed: 120 m / 15 m/s = 8 seconds.

AI explanation

Since the train and the bird are moving in opposite directions, their relative speed is the sum of their individual speeds, which is 10 m/s + 5 m/s = 15 m/s. The time taken for the bird to cross the train is calculated by dividing the length of the train by this relative speed. Therefore, the time taken is 120 m / 15 m/s, which equals 8 seconds.

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