A skateboarder begins at rest, accelerates uniformly to a speed of 8ms−1 in 5s, maintains this speed for the next 3s, and then comes to rest with uniform retardation in the following 2s.
(a) Draw the velocity–time graph for the motion, clearly indicating all time instants and speed values.
(b) From the graph, calculate the distance travelled in each stage and hence obtain the total distance covered.
(c) Determine the numerical value of acceleration in the first stage and that of retardation in the last stage.
(d) Compute the average speed for the whole 10s motion.