Question

A body travels a distance of 3 km towards East, then 4 km towards North and finally 9 km towards East.
(i) What is the total distance travelled?
(ii) What is the resultant displacement?

Answer 1

1-22-57
(i) Distance travelled is the actual path covered.
Total distance travelled:
= (3 + 4 + 9) km
= 16 km

(ii) The body travels a total distance of 12 km east, which means towards the x-axis, on a Cartesian plane. It travels a distance of 4 km in north direction, which means towards y-axis.
Resultant displacement:
$$\begin{gathered} \sqrt{{12}^2+4^2} \\ =\sqrt{144+16} \\ =\sqrt{160} \\ =\boxed{12.65\mathrm{km}} \end{gathered}$$