Thank you for reporting, we will resolve it shortly
Q.
A body goes $20\, km$ north and then $10 \,km$ due east. The displacement of body from Us starting point is:
AFMCAFMC 2003
Solution:
Body goes $20 \,km$ due north along $\overrightarrow{ OA }$ and then $10\, km$ due east along $\overrightarrow{ AB }$
Net displacement $=\sqrt{(O A)^{2}+(A B)^{2}}$
$=\sqrt{(20)^{2}+(10)^{2}}$
$=\sqrt{400+100}$
$=10 \sqrt{5} km =22.36 \,km$
