Question

A particle moves 3 metre North then 4 metre east and finally 6 South calculate the distance travelled and displacement​

Answer 1

distance = 13 m

displacement = 5 m

Answer 2

Distance travelled is calculated by adding all the distances .

d = 3 m + 4 m + 6 m

⇒ d = 13 m

The distance travelled is 13 m .

The particle travels 3 m North and then 6 m south .

So his net displacement is now 3 m south .

Then the particle also travels 4 m east .

So the angle between the two vectors of south and east is 90° .

Hence resultant displacement is :

$\sqrt{A^2+B^2+2ABcos90^\circ}\\\\\implies \sqrt{A^2+B^2}\\\\\implies \sqrt{3^2+4^2}\\\\\implies \sqrt{25}\\\\\implies 5$

The resultant displacement is 5 m south east.