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Well, I am sorta stuck on this problem:

Two trains, one traveling at 78 km/h and the other at 135 km/h, are headed toward one another along a straight, level track. When they are 980 m apart, each engineer sees the other's train and applies the brakes. The brakes decelerate each train at the rate of 1.0 m/s^2.

(a) What is the braking distance for the first train?

(b) What is the braking distance for the second train?

(c) Do they both collide? Yes or No.

This is what I did:

For the first part, since the original distance between the trains wasn't 980m, I decided to draw a diagram where they both apply the breaks and with the lease distance between them as 980m. So, I kept the initial position as 980m and tried to figure out the final position (where the first train stops), then took the final velocity as zero. I then applied the [v(t) = at+ v initial] and found t = 21.6s after converting the speed of the first train to m/s. Then I plugged that into the second equation for constant acceleration and ended up with 1213.28m, which I think is ridiculous. What am I doing wrong here? Of course, I can find out the answers for two and three once I get the first part. Any help or hints appreciated.

Edd.

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