1. The problem statement, all variables and given/known data A train is at 0 m/s at the begining. It accelerates on a distance of 60 m, after it goes on a constant speed on the next 120 m and it finally decelerates on the next on 30 m and stops. The whole traject is 25 sec. Find the constant speed. 2. Relevant equations x final = x initial + v initial * t + 1/2 * a * t^2 3. The attempt at a solution 60 = 0 + 0 + 1/2* a* t^2 60 = 1/2 * a * t^2 We also know that the first traject goes from 0 to 60 m and from 60 to 180 m and finally from 180 to 210 m.