Q. A person moves $30\,m $ north and then $ 20\,m $ towards east and finally $4\, m/s ^{2}$ south-west direction. The displacement of the person from the origin will be
J & K CETJ & K CET 2004
Solution:
Taking the starting point as $O$,
we have $30\, m$ north $OA,\, 20\, m$ east $AB$,
and finally $30 \sqrt{2} m(S-E) BD$.
From $\Delta C AB,\, AC=20\, m,\, O\, C= 10\, m$
ln $\Delta OCD,\, OD=OC,\, OD=10\, m$
Hence, final displacement from origin is $10\, m$.
