Initial speed of the train = 7 m/s Final speed of the train = 17 m/s Change of speed of the train = (17 - 7) m/s = 10 m/s Time taken for the change of the speed of the train = 120 s Then Acceleration of the train = Change of speed of the train/Time taken for the change of speed = 10/120 m/s^2 = 1/12 m/s^2 = 0.083 m/s^2 So the acceleration of the train is 1/12 meter per second square or 0.083 m/s^2. I hope this is the answer you were looking for.
