- #1

SharkFin39

- 2

- 0

## Homework Statement

Two trains, one traveling at 74.00 km/h and the other at 148.00 km/h, are headed toward one another along a straight, level track. When they are 938 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/s2. Is there a collision? What distance do the trains need to allow between them to stop at this acceleration? What acceleration do the two trains need to have to stop exactly in a distance of 938 m?

## Homework Equations

V^2 - Vo^2 = 2a(X-Xo) (this is what I used to solve parts 1 and 2)

## The Attempt at a Solution

Well, I had no problem with the first two parts of the question. Using the above formula I determined that the first train needed 211.275m to stop, and the second needed 845.057m to stop. They needed a total distance of 1056.332m to stop, therefore there was a collision.

My question is how would I go about solving the third part of the question. The question calls for a single answer in m/s^2. Otherwise, I would've just divided the 938m by 2, and solved for two separate accelerations. I think I'm actually more stumped by the question than the calculations. If this makes sense to anyone, I'd really appreciate some guidance. Thank you in advance for you assistance.

SharkFin