Question

A dog searching for a bone walks 3.5 m south, then 8.20 m at an angle 30.0 north of east, and finally 15.0 m west. Using graphical techniques, find the dogs resultant displacement vector.

Answer 1

8.2 at NE = 5.8N and 5.8E

(0,-3.5)+(5.8,5.8)+(-15,0) = (-9.2,2.3)

(a) sqrt(9.2^2 + 2.3^2) = 9.48
(b) arctan(2.3/-9.2) = 166 deg

Answer 2

How come is the vector 8.2 defined into 5.8 N and 5.8 E ??. It's declared that the angle is 30° so it must be 7.1 E and 4.1 N.