Two trains run in the same direction. The one behind has double the length of the one ahead. The initial distance of separation
1 answer:
Answer:
The shorter train has a length of 600m
Explanation:
The equation of motion of the first train can be written as:
(1)
v' = 108km/h = 30m/s
Furthermore, you can write the equation of motion of the second train as:
= xo + vt (2)
v = 36km/h = 10m/s
where you have taken the initial position as measured from the front of the first train to the front of the second one. l is the length of the second train and 200 the separation of it respect to the first train.
For t = 40 both trains have the same position, that is, x=x'. Then, you equal equations (1) and (2), replace t=40, and solve the equation for l:
Hence, the first train has a length of 600 m
The train behind, or the second train, has twice the length of the first train:
The shorter train has a length of 600m
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