Question

A boy has to go $50m$ due north, $40m$ due east and $20m$ due south to reach his home. What distance he has to walk to reach his home? What is the displacement from his home to the cafe?

Answer 1

Distance is the total path covered by the boy

Distance traveled by the $=50+40+20=110m$

Displacement is the shortest path between source (house) and destination (school) $=AB$

See the fig:

$BE=CD=40m$

$AE=AC-CE=50-20=30$

Now displacement,

$AB=\sqrt{A{E}^2+B{E}^2}$

$AB=\sqrt{{30}^2+{40}^2}=50m$