Question

Using following data, draw time – displacement graph for a moving object: Use this graph to find average velocity for first $ 4 \mathrm{s}$, for next $ 4 \mathrm{s}$ and for last $ 6 \mathrm{s}$.

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Answer 1

Step 1: Given

Time–displacement graph:

Step 2: To find

We have to find the average velocity for first $4\mathrm{s}$, for next $4\mathrm{s}$ and for last $6\mathrm{s}$.

Step 3: Finding the average velocity for first $4\mathrm{s}$

We know the formula,

$\mathrm{Average}\mathrm{velocity}=\frac{\mathrm{Change}\mathrm{in}\mathrm{displacement}}{\mathrm{Total}\mathrm{time}\mathrm{taken}}$

By substituting the values,

$$\begin{gathered} \mathrm{v}=\frac{4-0}{4-0} \\ =\frac{4}{4} \\ =1{\mathrm{ms}}^{-1} \end{gathered}$$

Step 4: Finding the average velocity for next $4\mathrm{s}$

$$\begin{gathered} \mathrm{v}=\frac{4-4}{8-4} \\ =\frac{0}{4} \\ =0 \end{gathered}$$

Step 5: Finding the average velocity for last $6\mathrm{s}$

$$\begin{gathered} \mathrm{v}=\frac{0-6}{16-10} \\ =-\frac{6}{6} \\ =-1{\mathrm{ms}}^{-1} \end{gathered}$$

Therefore, the average velocity for first $4\mathrm{s}$ is $1{\mathrm{ms}}^{-1}$, for next $4\mathrm{s}$ is $0$, and for last $6\mathrm{s}$ is $-1{\mathrm{ms}}^{-1}$.