Question

A person moves 30 m North and then 20 m towards East and finally $30\sqrt{2}$ m in South-West direction. The displacement of the person from the origin will be

• A. 10 m along North
• B. 10 m along South
• C. Zero
• D. 10 m along West

Answer 1

Answer: (D)

$30m$ North

$20m$ East

and the $30\sqrt{2}$ SW can be rewritten as $30m$ in south and $30m$ in West

because $south$ and $west$ being at ${90}^0$ result

in $\sqrt{{30}^2+{30}^2}=30\sqrt{2}$

so at last we have following data that in south $X_S=30m+north=30m+(-30m)=0$,

$negative$ becasue north is $opposite$ to south.

and in West we have $X_W=30m+east=30m+(-20m)=10m$

so the displacement is $10m$ due $west$