A man travels a distance of 1.5m towards east, then 2.0m towards south and finally 4.5m towards east.
(i) What is the total distance travelled? (ii) What is his resultant displacement?

(i) Total distance travelled = 1.5+2.0+4.5  = 8.0m(ii)To find the resultant displacement we should draw a map of the man's movements by choosing a convenient scale. Let 1cm represent 1m. Then 1.5m can be represented by 1.5cm long line, 2.0m by 2.0cm line and 4.5m by a 4.5cm long line.
Now, 1cm = 1m
So, 6.3 cm = 6.3m            We draw a 1.5cm long line AB from west to east to represent 1.5m towards east. Then we draw a 2.0cm long line BC towards south to represent 2.0m towards south. And finally we draw a third line CD, 4.5cm long, towards east to represent a distance of 4.5m towards east. Now, the resultant displacement can be found by joining the starting point A with the finishing point D. Thus, the line AD represents the final displacement of the man. Let us measure the length of line AD. It is found to be 6.3cm. Thus, the final displacement as represented by AD is 6.3metres. So, whenever a body travels along a zigzag, the final displacement is obtained by joining the starting point and the finishing point of the body by a straight line.