Acceleration, in physics, is the rate of change of velocity of an object with respect to time. Anytime an object's velocity is changing, the object is said to be accelerating. From the graph, the speeding up phase would from 0.1 s to 0.15 s. Therefore, we calculate the acceleration by the slope of the line,
Acceleration = 0.8 - 0 / 0.15 - 0.1
Acceleration = 16 m/s^2