Question

on his fishing trip Justine takes the boat 12 km south. The fish aren't biting so he goes 4 km west. He follows a school of fish 1 km north. What distance did he cover? What was his displacement?

Answer 1

[ Please make a chart by following the directions on your own, 'cause it's hard to explain, here (only directions), magnitudes and answers are here ] :

Distance = 12 + 4+ 1 = 17 Km
[Just add all the values ]

Displacement, Now, if you'll look at your triangle, which has formed by his directions, perpendicular is 11, base is 4, & you need to calculate that hypotenuse which is your displacement.

So, apply Pythagoras Theorem here:
H² = P² + B²
H² = 11² + 4²
H²= 121 + 16
H = √137= 11.70 Km

In short, Distance = 17 Km and Displacement = 11.70 Km

Hope this helps!