A boy starts from point A, walks straight to point B at a uniform speed of 1.2 m/s covering 60 m, rests there for 10 s, and then runs back towards A at a uniform speed of 2 m/s until he reaches the starting point.
a. (a) Draw the displacement–time graph for the whole journey, taking A as the origin.
b. (b) On your graph, mark the instant at which the boy turns back towards A.