Two trains of equal lengths take 13 seconds and 26 seconds, respectively, to cross a pole. If these trains are moving in the same direction, then how long will they take to cross each other?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 52 seconds.
Time taken by first train to cross the pole = 13 sec
Time taken by second train to cross the pole = 26 sec
Let the length of the trains be L meter
According to the given question,
The speed of the first train (x) = (L/13) m/s
The speed of the second train (y) = (L/26) m/s
The speed when they cross each other in the same direction = x - y
⇒ (L/13) - (L/26) = (L/26) m/s
Hence, the time taken when they cross each other in the same direction =
⇒ 2L/(L/26) seconds = 52 seconds