Question

Using the following data, draw the displacement$-$time graph for a moving object:



From the graph, find the average velocity for the first $4~\text s$, for the next $4~\text s$ and the last $6~\text s$.
[5 Marks]
\begin{tabular}{llllllllll} Time (s) & 0 & 2 & 4 & 6 & 8 & 10 & 12 & 14 & 16 \\ \hline Displacement (m) & 0 & 2 & 4 & 4 & 4 & 6 & 4 & 2 & 0 \end{tabular}

Answer 1

Average velocity for first 4 s.
Average velocity = $\frac{changeindisplacement}{Totaltimetaken}$
$v=\frac{4-0}{4-0}=\frac{4}{4}=1m{s}^{-1}$
For next 4 s, $v=\frac{4-4}{8-4}=\frac{0}{4}=0m{s}^{-1}$
(or as x remains the same from 4 to 8 seconds, velocity is zero)
For last 6 s, $v=\frac{0-6}{16-10}=-1m{s}^{-1}$