Passing Trains
At the moment at which they are passing each other, both moving trains are 200ft apart from one another (distance separating the two parallel tracks). If Train A is traveling East at 50 ft/sec and Train B is traveling West at 10ft/sec, how far apart will the Trains be after 9 seconds?
The answer is 575.85.
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1 solution
At the moment they are passing we get a situation like the one presented to us in the diagram. Since train a is moving 50 ft/sec it will have traveled 450 ft to the East after 9 seconds. Similarly Train b has traveled 90 ft to the West during that time. We can construct a triangle and use the Pythagorean theorem to solve for the final distance between A and B after 9 seconds:
b = 4 5 0 + 9 0 = 5 4 0 a = 2 0 0 h y p = a 2 + b 2 = 5 7 5 . 8 5