To calculate the average acceleration, draw a straight line (shown in green) and find the gradient. Remember, gradient = acceleration. Acceleration = (15 – 0) ÷ (120 – 60) = 0.25 m/s 2 .

For example, the graph below could be used to calculate the average rate over any period of time. Using this graph, we can calculate the average rate between 30 seconds and 120 seconds. \ ...