Question

A man walks $30m$ towards north, then $20m$, towards east and in the last $30\sqrt{2}m$, towards south-west. The displacement from origin is:

• A. $10m$ towards west
• B. $10m$ towards east
• C. $60\sqrt{2}m$ towards northwest
• D. $60\sqrt{2}m$ towards east north

Answer 1

The correct option is A $10m$ towards west

In vector form:

$\overrightarrow{S}=30\hat{j}+20\hat{i}+30\sqrt{2}\cos {45}^o(-\hat{i})+30\sqrt{2}\sin {45}^o(-\hat{j})$

$=30\hat{j}+20\hat{i}-30\hat{i}-30\hat{j}$

$=10\hat{i}$

$\therefore$ Displacement is $10m$ towards west