Question

A man goes $12\text{m}$ towards North, then $5\text{m}$ towards east. Then, total length of displacement is

• A. $13\text{m}$
• B. $15\text{m}$
• C. $12\text{m}$
• D. $5\text{m}$

Answer 1

The correct option is A $13\text{m}$

Let x-axis and y-axis representing east and north directions respectively.
Let $\overrightarrow{r}$ represents the position vector of man from the origin.
$\Rightarrow \overrightarrow{r}=5\hat{i}+12\hat{j}$
$\therefore$ Displacement of man = $\left|\overrightarrow{r}\right|=\sqrt{5^2+{12}^2}=13\text{m}$