Question

Jenny runs 1 mi to the northeast then 1 mi south. Graphically find her net displacement

Answer 1

from OA=AB

\theta +\theta 45=180

2\theta =180-45

\theta =\frac{180-45}{2}=67.5

from sin rule,

\frac{OA}{sin\theta }=\frac{AB}{sin\theta }=\frac{OB}{sin45}

\therefore \frac{1}{sin67.5}=\frac{1}{sin67.5}=\frac{OB}{sin45}

\therefore OB=\frac{sin45}{sin67.5}=0.765366864730ml

\therefore net displacement OB=o.77ml