The position of an object changes from $\overrightarrow{r}=(2\hat{i}+\hat{j})m$ to $\overrightarrow{r}=(4\hat{i}+3\hat{j})m$ in $2s$. Find its average velocity.

Distance between two points $=\sqrt{(x_2-x_1{)}^2+(y_2-y_1{)}^2}$

In this case ,displacement $s=\sqrt{(4-2{)}^2+(3-1{)}^2}$

$s=\sqrt{2^2+2^2}$

$s=\sqrt{8}$

$s=2\sqrt{2}$

Now, average velocity= displacement/time

$v=\frac{2\sqrt{2}}{2}$

$v=\sqrt{2}$