Answer:
Vf = 10.76 m/s
Explanation:
Train kinematics
The train moves with uniformly accelerated movement
Formula (1)
Vf: Final speed (m/s)
V₀: Inital speed (m/s)
t: time in seconds (s)
a: acceleration (m/s²)
Movement from t = 0 to t = 5.2s
We replace in formula (1)
4.6 = 0 + a*5.2
a = 4.6/5.2 = 0.88 m/s²
Movement from t = 5.2s to t = 5.2s + 7s = 12.2s
We replace in formula (1)
Vf = 10.76 m/s