Two freight trains, both 250 m long, are heading towards each other at the same speed of 45 km / h.

Two freight trains, both 250 m long, are heading towards each other at the same speed of 45 km / h. How many seconds will pass after the drivers have met before the conductors of the last cars meet?

1) To solve this task, you must first find the distance between the conductors:
2) 250 + 250 = 500m.
3) Now we will find the speed of the convergence of trains and convert their speed to m / s:
4) 45 + 45 = 90km / h = 90 * 1000: 3600 = 90000: 3600 = 25m / s.
5) Now let’s calculate how many seconds the conductors of the last cars will meet using the formula t = S: v.
6) 500: 25 = 20s.
Answer: in 20 seconds the conductors will meet.